
<PAGE>
 
                                                                    Exhibit 1.2

- --------------------------------------------------------------------------------
- --------------------------------------------------------------------------------


                            BOSTON PROPERTIES, INC.
                            (a Delaware corporation)



                        6,280,000 Shares of Common Stock



                        INTERNATIONAL PURCHASE AGREEMENT



Dated:  June   , 1997


- --------------------------------------------------------------------------------
- --------------------------------------------------------------------------------
<PAGE>
 
                               Table of Contents
<TABLE>
<CAPTION>
 
<S>                                                                          <C>
SECTION 1.  Representations and Warranties..................................   4
    (a)  Representations and Warranties by the Company......................   4
           (i)  Compliance with Registration Requirements....................  4
           (ii)  Independent Accountants.....................................  5
           (iii)  Financial Statements.......................................  5
           (iv)  No Material Adverse Change in Business......................  6
           (v)  Good Standing of the Company.................................  6
           (vi)  Good Standing of Subsidiaries...............................  6
           (vii)  Good Standing of Property Partnerships.....................  7
           (viii)  Capitalization............................................  7
           (ix)  Authorization of Agreement..................................  7
           (x)  Authorization and Description of Securities..................  8
           (xi)  Authorization of the Operating Partnership Agreement........  8
           (xii)  Authorization and Description of OP Units..................  8
           (xiii)  Absence of Defaults and Conflicts.........................  8
           (xiv)  Authorization of the Formation Transaction Documents....... 10
           (xv)  Absence of Labor Dispute.................................... 10
           (xvi)  Absence of Proceedings..................................... 10
           (xvii)  Qualification as a REIT................................... 10
           (xviii)  Accuracy of Exhibits..................................... 10
           (xix)  New York Stock Exchange Listing............................ 10
           (xx)  Absence of Further Requirements............................. 10
           (xxi)  Possession of Licenses and Permits......................... 11
           (xxii)  The Properties............................................ 11
           (xxiii)  Insurance................................................ 12
           (xxiv)  Taxes..................................................... 12
           (xxv)  Mortgages and Deeds of Trust............................... 12
           (xxvi)  Compliance with Cuba Act.................................. 12
           (xxvii)  Investment Company Act................................... 12
           (xxviii)  Environmental Laws...................................... 13
           (xxix)  Registration Rights....................................... 14
     (b)   Officer's Certificates............................................ 14
 
SECTION 2. Sale and Delivery to International Managers; Closing.............. 14
     (a)   Initial Securities................................................ 14
     (b)   Option Securities................................................. 14
     (c)   Payment........................................................... 15
     (d)   Denominations; Registration....................................... 15
 
SECTION 3. Covenants of the Company.......................................... 16
     (a)   Compliance with Securities Regulations and Commission Requests.... 16
     (b)   Filing of Amendments.............................................. 16
</TABLE>

                                       i
<PAGE>
 
<TABLE>
<S>                                                                          <C>
     (c)   Delivery of Registration Statements............................... 16
     (d)   Delivery of Prospectuses.......................................... 17
     (e)   Continued Compliance with Securities Laws......................... 17
     (f)   Blue Sky Qualifications........................................... 17
     (g)   Rule 158.......................................................... 18
     (h)   Use of Proceeds................................................... 18
     (i)   Listing........................................................... 18
     (j)   Restriction on Sale of Securities................................. 18
     (k)   Lock-up Agreements................................................ 18
     (l)   Qualification as a REIT........................................... 19
     (m)   Compliance with NASD Rules........................................ 19
     (n)   Compliance with Rule 463.......................................... 19
 
SECTION 4. Payment of Expenses............................................... 19
     (a)   Expenses.......................................................... 19
     (b)   Termination of Agreement.......................................... 20
 
SECTION 5. Conditions of International Managers' Obligations................. 20
     (a)   Effectiveness of Registration Statement........................... 20
     (b)   Opinion of Counsel for Company.................................... 20
     (c)   Opinion of Counsel for International Managers..................... 20
     (d)   Opinion of Counsel for International Managers..................... 20
     (e)   Officers' Certificate............................................. 21
     (f)   Accountant's Comfort Letter....................................... 21
     (g)   Bring-down Comfort Letter......................................... 21
     (h)   Approval of Listing............................................... 21
     (i)   No Objection...................................................... 22
     (j)   Lock-up Agreements................................................ 22
     (k)   Purchase of Initial U.S. Securities............................... 22
     (l)   Conditions to Purchase of International Option Securities......... 22
           (i)  Officers' Certificate........................................ 22
           (ii)  Opinion of Counsel for Company.............................. 22
           (iii)  Opinion of General Counsel of Company...................... 22
           (iv)  Opinion of Counsel for International Managers............... 23
           (v)  Bring-down Comfort Letter.................................... 22
     (m)   Additional Documents.............................................. 23
     (n)   Termination of Agreement.......................................... 23
 
SECTION 6. Indemnification................................................... 23
     (a)   Indemnification of International Managers......................... 23
     (b)   Indemnification of Company, Directors and Officers................ 24
     (c)   Actions against Parties; Notification............................. 25
     (d)   Settlement without Consent if Failure to Reimburse................ 25
     (e)   Indemnification for Reserved Securities........................... 26
</TABLE>

                                      ii
<PAGE>
 
<TABLE>
<S>                                                                          <C>
SECTION 7. Contribution...................................................... 26

SECTION 8. Representations, Warranties and Agreements to Survive Delivery.... 27

SECTION 9. Termination of Agreement.......................................... 27
     (a)   Termination; General.............................................. 27
     (b)   Liabilities....................................................... 28
 
SECTION 10.  Default by One or More of the International Managers............ 28
 
SECTION 11.  Notices......................................................... 29
 
SECTION 12.  Parties......................................................... 29
 
SECTION 13.  GOVERNING LAW AND TIME.......................................... 29
 
SECTION 14.  Effect of Headings.............................................. 29
</TABLE>

                                      iii
<PAGE>
 
                            BOSTON PROPERTIES, INC.

                            (a Delaware corporation)

                        6,280,000 Shares of Common Stock

                           (Par Value $.01 Per Share)

                        INTERNATIONAL PURCHASE AGREEMENT
            
                                                            June  , 1997


MERRILL LYNCH INTERNATIONAL
GOLDMAN SACHS INTERNATIONAL
BEAR, STEARNS INTERNATIONAL LIMITED
MORGAN STANLEY & CO. INTERNATIONAL LIMITED
PAINEWEBBER INTERNATIONAL (UK) LTD.
PRUDENTIAL-BACHE SECURITIES (U.K.) INC.
SMITH BARNEY INC.
 as Lead Managers of the several International Managers
c/o  Merrill Lynch International
Ropemaker Place
25 Ropemaker Street
London EC2Y 9LY
England

Ladies and Gentlemen:

     Boston Properties, Inc., a Delaware corporation (the "Company") and Boston
Properties Limited Partnership, a Delaware limited partnership (the "Operating
Partnership"), each confirms its agreement with Merrill Lynch International
("Merrill Lynch (Int'l)"), Goldman Sachs International ("Goldman Sachs
(Int'l)"), Bear, Stearns International Limited ("Bear, Stearns (Int'l)"), Morgan
Stanley & Co. International Limited ("Morgan Stanley (Int'l)"), PaineWebber
International (UK) Ltd. ("PaineWebber (Int'l)"), Prudential-Bache Securities
(U.K.) Inc. ("Prudential-Bache (Int'l)"), Smith Barney Inc. ("Smith Barney") and
each of the other international underwriters named in Schedule A hereto
(collectively, the "International Managers", which term shall also include any
underwriter substituted as hereinafter provided in Section 10 hereof), for whom
Merrill Lynch (Int'l), Goldman Sachs (Int'l), Bear, Stearns (Int'l), Morgan
Stanley (Int'l), PaineWebber (Int'l), Prudential-Bache (Int'l) and Smith Barney

                                       1
<PAGE>
 
are acting as representatives (in such capacity, the "Lead Managers"), with
respect to the issue and sale by the Company and the purchase by the
International Managers, acting severally and not jointly, of the respective
numbers of shares of Common Stock, par value $.01 per share, of the Company
("Common Stock") set forth in said Schedule A, and with respect to the grant by
the Company to the International Managers, acting severally and not jointly, of
the option described in Section 2(b) hereof to purchase all or any part of
942,000 additional shares of Common Stock to cover over-allotments, if any.  The
aforesaid 6,280,000 shares of Common Stock (the "Initial International
Securities") to be purchased by the International Managers and all or any part
of the 942,000 shares of Common Stock subject to the option described in Section
2(b) hereof (the "International Option Securities") are hereinafter called,
collectively, the "International Securities".

     It is understood that the Company and the Operating Partnership are
concurrently entering into an agreement dated the date hereof (the "U.S.
Purchase Agreement") providing for the offering by the Company of an aggregate
of 25,120,000 shares of Common Stock (the "Initial U.S. Securities") through
arrangements with certain underwriters in the United States and Canada (the
"U.S. Underwriters") for which Merrill Lynch & Co., Merrill Lynch, Pierce,
Fenner & Smith Incorporated, Goldman Sachs & Co., Bear, Stearns & Co. Inc.,
Morgan Stanley & Co. Incorporated, PaineWebber Incorporated, Prudential
Securities Incorporated and Smith Barney Inc. are acting as representatives (the
"U.S. Representatives") and the grant by the Company to the U.S. Underwriters,
acting severally and not jointly, of an option to purchase all or any part of
the U.S. Underwriters' pro rata portion of up to 3,768,000 additional shares of
Common Stock solely to cover overallotments, if any (the "U.S. Option
Securities" and, together with the International Option Securities, the "Option
Securities").  The Initial U.S. Securities and the U.S. Option Securities are
hereinafter called the "U.S. Securities".  It is understood that the Company is
not obligated to sell, and the International Managers are not obligated to
purchase, any Initial International Securities unless all of the Initial U.S.
Securities are contemporaneously purchased by the U.S. Underwriters.

     The International Managers and the U.S. Underwriters are hereinafter
collectively called the "Underwriters", the Initial International Securities and
the Initial U.S. Securities are hereinafter collectively called the "Initial
Securities", and the International Securities and the U.S. Securities are
hereinafter collectively called the "Securities".

     The Underwriters will concurrently enter into an Intersyndicate Agreement
of even date herewith (the "Intersyndicate Agreement") providing for the
coordination of certain transactions among the Underwriters under the direction
of Merrill Lynch & Co., Merrill Lynch, Pierce, Fenner & Smith Incorporated and
Goldman, Sachs & Co. (in such capacity, the "Global Coordinators").

     The Company and the Operating Partnership each understand that the
International Managers propose to make a public offering of the International
Securities as soon as the Lead Managers deem advisable after this Agreement has
been executed and delivered.

                                       2
<PAGE>
 
     The Company and the International Managers agree that up to [       ]
shares of the Initial International Securities to be purchased by the
International Managers and that up to [750,000] shares of the Initial U.S.
Securities to be purchased by the U.S. Underwriters (collectively, the "Reserved
Securities") shall be reserved for sale by the Underwriters to certain eligible
employees and persons having business relationships with the Company, as part of
the distribution of the Securities by the Underwriters, subject to the terms of
this Agreement, the applicable rules, regulations and interpretations of the
National Association of Securities Dealers, Inc. and all other applicable laws,
rules and regulations.  To the extent that such Reserved Securities are not
orally confirmed for purchase by such eligible employees and persons having
business relationships with the Company by the end of the first business day
after the date of this Agreement, such Reserved Securities may be offered to the
public as part of the public offering contemplated hereby.

     The Company has filed with the Securities and Exchange Commission (the
"Commission") a registration statement on Form S-11 (No. 333-25279) covering the
registration of the Securities under the Securities Act of 1933, as amended (the
"1933 Act"), including the related preliminary prospectus or prospectuses.
Promptly after execution and delivery of this Agreement, the Company will either
(i) prepare and file a prospectus in accordance with the provisions of Rule 430A
("Rule 430A") of the rules and regulations of the Commission under the 1933 Act
(the "1933 Act Regulations") and paragraph (b) of Rule 424 ("Rule 424(b)") of
the 1933 Act Regulations or (ii) if the Company has elected to rely upon Rule
434 ("Rule 434") of the 1933 Act Regulations, prepare and file a term sheet (a
"Term Sheet") in accordance with the provisions of Rule 434 and Rule 424(b).
Two forms of prospectus are to be used in connection with the offering and sale
of the Securities:  one relating to the International Securities (the "Form of
International Prospectus") and one relating to the U.S. Securities (the "Form of
U.S. Prospectus").  The Form of International Prospectus is identical to the
Form of U.S. Prospectus, except for the front cover and back cover pages and the
information under the caption "Underwriting."  The information included in any
such prospectus or in any such Term Sheet, as the case may be, that was omitted
from such registration statement at the time it became effective but that is
deemed to be part of such registration statement at the time it became effective
(a) pursuant to paragraph (b) of Rule 430A is referred to as "Rule 430A
Information" or (b) pursuant to paragraph (d) of Rule 434 is referred to as
"Rule 434 Information."  Each Form of International Prospectus and Form of U.S.
Prospectus used before such registration statement became effective, and any
prospectus that omitted, as applicable, the Rule 430A Information or the Rule
434 Information, that was used after such effectiveness and prior to the
execution and delivery of this Agreement, is herein called a "preliminary
prospectus."  Such registration statement, including the exhibits thereto and
schedules thereto at the time it became effective and including the Rule 430A
Information and the Rule 434 Information, as applicable, is herein called the
"Registration Statement."  Any registration statement filed pursuant to Rule
462(b) of the 1933 Act Regulations to register additional shares of Common Stock
to be sold in the public offering of the Securities is herein referred to as the
"Rule 462(b) Registration Statement," and after such filing the term
"Registration Statement" shall include the Rule 462(b) Registration Statement.
The final Form of International Prospectus and the final Form of U.S. Prospectus
in the forms first furnished to the Underwriters for use in connection with the

                                       3
<PAGE>
 
offering of the Securities are herein called the "International Prospectus" and
the "U.S. Prospectus," respectively, and collectively, the "Prospectuses."  If
Rule 434 is relied on, the terms "International Prospectus" and "U.S.
Prospectus" shall refer to the preliminary International Prospectus dated June
10, 1997 and preliminary U.S. Prospectus dated June 10, 1997 respectively, each
together with the applicable Term Sheet and all references in this Agreement to
the date of such Prospectuses shall mean the date of the applicable Term Sheet.
For purposes of this Agreement, all references to the Registration Statement,
any preliminary prospectus, the International Prospectus, the U.S. Prospectus or
any Term Sheet or any amendment or supplement to any of the foregoing shall be
deemed to include the copy filed with the Commission pursuant to its Electronic
Data Gathering, Analysis and Retrieval system ("EDGAR").

     At or prior to Closing Time (as hereinafter defined), the Company will
complete a series of transactions (the "Formation Transactions") described in
the Prospectuses under the caption "Structure and Formation of the Company--
Formation Transactions."  As part of the Formation Transactions (i) certain
Property Partnerships (as defined in the Registration Statement) will contribute
properties to the Operating Partnership, or will merge into the Operating
Partnership, in exchange for units of limited partnership of the Operating
Partnership ("OP Units"), (ii) certain persons will contribute their direct and
indirect interests in certain Property Partnerships to the Operating Partnership
or its designee in exchange for OP Units, (iii) the Company will contribute a
portion of its third-party management business to Boston Properties Management,
Inc. (the "Development and Management Company"), a subsidiary of the Operating
Partnership, in exchange for OP Units, and (iv) the Company will contribute the
net proceeds from the public offering of the Securities to the Operating
Partnership in exchange for OP Units.

     SECTION 1.  Representations and Warranties.
                 ------------------------------ 

     (a)  Representations and Warranties by the Company.  The Company and the
Operating Partnership each severally represents and warrants to each
International Manager as of the date hereof, as of the Closing Time referred to
in Section 2(c) hereof, and as of each Date of Delivery (if any) referred to in
Section 2(b) hereof, and agrees with each International Manager, as follows:

            (i)  Compliance with Registration Requirements.  Each of the
                 -----------------------------------------              
     Registration Statement and any Rule 462(b) Registration Statement has
     become effective under the 1933 Act and no stop order suspending the
     effectiveness of the Registration Statement or any Rule 462(b) Registration
     Statement has been issued under the 1933 Act and no proceedings for that
     purpose have been instituted or are pending or, to the knowledge of the
     Company, are contemplated by the Commission, and any request on the part of
     the Commission for additional information has been complied with.

            At the respective times the Registration Statement, any Rule 462(b)
     Registration Statement and any post-effective amendments thereto became
     effective and at the Closing Time (and, if any International Option
     Securities are purchased, at the Date of Delivery),

                                       4
<PAGE>
 
     the Registration Statement, the Rule 462(b) Registration Statement and any
     amendments and supplements thereto complied and will comply in all material
     respects with the requirements of the 1933 Act and the 1933 Act Regulations
     and did not and will not contain an untrue statement of a material fact or
     omit to state a material fact required to be stated therein or necessary to
     make the statements therein not misleading, and the Prospectuses, any
     preliminary prospectuses and any supplement thereto or prospectus wrapper
     prepared in connection therewith, at their respective times of issuance and
     at the Closing Time, complied and will comply in all material respects with
     any applicable laws or regulations of foreign jurisdictions in which the
     Prospectuses and such preliminary prospectuses, as amended or supplemented,
     if applicable, are distributed in connection with the offer and sale of
     Reserved Securities.  Neither of the Prospectuses nor any amendments or
     supplements thereto (including any prospectus wrapper), at the time the
     Prospectuses or any amendments or supplements thereto were issued and at
     the Closing Time (and, if any International Option Securities are
     purchased, at the Date of Delivery), included or will include an untrue
     statement of a material fact or omitted or will omit to state a material
     fact necessary in order to make the statements therein, in light of the
     circumstances under which they were made, not misleading.  If Rule 434 is
     used, the Company will comply with the requirements of Rule 434 and the
     Prospectuses shall not be "materially different", as such term is used in
     Rule 434, from the prospectuses included in the Registration Statement at
     the time it became effective.  The representations and warranties in this
     subsection shall not apply to statements in or omissions from the
     Registration Statement or the International Prospectus made in reliance
     upon and in conformity with information furnished to the Company in writing
     by any International Manager through the Lead Managers expressly for use in
     the Registration Statement or the International Prospectus.

          Each preliminary prospectus and the prospectuses filed as part of the
     Registration Statement as originally filed or as part of any amendment
     thereto, or filed pursuant to Rule 424 under the 1933 Act, complied when so
     filed in all material respects with the 1933 Act Regulations and each
     preliminary prospectus and the Prospectuses delivered to the Underwriters
     for use in connection with this offering was identical to the
     electronically transmitted copies thereof filed with the Commission
     pursuant to EDGAR, except to the extent permitted by Regulation S-T.

          (ii)   Independent Accountants.  The accountants who certified the
                 -----------------------                                    
     financial statements and supporting schedules included in the Registration
     Statement are independent public accountants as required by the 1933 Act
     and the 1933 Act Regulations.

          (iii)  Financial Statements.  The combined financial statements
                 --------------------                                    
     included in the Registration Statement and the Prospectuses, together with
     the related schedules and notes, present fairly the financial position of
     the Boston Properties Predecessor Group (as defined in the Registration
     Statement) at the dates indicated, and the combined statements of
     operations, owners' equity and cash flows of the Boston Properties

                                       5
<PAGE>
 
     Predecessor Group for the periods specified; said financial statements have
     been prepared in conformity with generally accepted accounting principles
     ("GAAP") applied on a consistent basis throughout the periods involved.
     The supporting schedules included in the Registration Statement present
     fairly in accordance with GAAP the information required to be stated
     therein.  The unaudited pro forma condensed consolidated financial
     statements and the related notes thereto included in the Registration
     Statement and the Prospectuses present fairly the information shown
     therein, have been prepared in accordance with the Commission's rules and
     guidelines with respect to pro forma financial statements and have been
     properly compiled on the bases described therein, and the assumptions used
     in the preparation thereof are reasonable and the adjustments used therein
     are appropriate to give effect to the transactions and circumstances
     referred to therein.  The selected financial data and the summary financial
     information included in the Prospectuses present fairly the information
     shown therein and have been compiled on a basis consistent with that of the
     audited financial statements included in the Registration Statement.  Other
     than the historical and pro forma financial statements (and schedules)
     included in the Registration Statement and Prospectuses, no other
     historical or pro forma financial statements (or schedules) are required by
     the 1933 Act or the 1933 Act Regulations to be included therein.

          (iv)  No Material Adverse Change in Business.  Since the respective
                --------------------------------------                       
     dates as of which information is given in the Registration Statement and
     the Prospectuses, except as otherwise stated therein, (A) there has been no
     material adverse change in the condition, financial or otherwise, or in the
     earnings, business affairs or business prospects of the Company, the
     Operating Partnership or the Subsidiaries (as hereinafter defined)
     considered as one enterprise, whether or not arising in the ordinary course
     of business (a "Material Adverse Effect"), (B) no material casualty loss or
     material condemnation or other material adverse event with respect to any
     of the properties set forth in Schedule C hereto has occurred, (C) there
     have been no transactions entered into by the Company, the Operating
     Partnership or any of the Subsidiaries, other than those in the ordinary
     course of business, which are material with respect to the Company, the
     Operating Partnership and the Subsidiaries considered as one enterprise,
     and (D) there has been no dividend or distribution of any kind declared,
     paid or made by the Company on any class of its capital stock or by the
     Operating Partnership or any of its Subsidiaries with respect to its
     partnership interests or any class of its capital stock.

          (v)  Good Standing of the Company.  The Company has been duly
               ----------------------------                            
     organized and is validly existing as a corporation in good standing under
     the laws of the State of Delaware and has corporate power and authority to
     own, lease and operate its properties and to conduct its business as
     described in the Prospectuses and to enter into and perform its obligations
     under this Agreement; and the Company is duly qualified as a foreign
     corporation to transact business and is in good standing in each other
     jurisdiction in which such qualification is required, whether by reason of
     the ownership or leasing of property or the conduct of business, except
     where the failure so to qualify or to be in good standing would not result
     in a Material Adverse Effect.

                                       6
<PAGE>
 
          (vi)   Good Standing of Subsidiaries.  Each of the subsidiaries of the
                 -----------------------------                                  
     Company, including without limitation the Operating Partnership and the
     Development and Management Company, (each a "Subsidiary" and, collectively,
     the "Subsidiaries") has been duly organized and is validly existing as a
     general or limited partnership or corporation, as the case may be, in good
     standing (in the case of corporations and limited partnerships) under the
     laws of the jurisdiction of its organization, has partnership or corporate
     power and authority, as the case may be, to own, lease and operate its
     properties and to conduct its business as described in the Prospectuses and
     is duly qualified as a foreign partnership or corporation to transact
     business and is in good standing in each jurisdiction in which such
     qualification is required, whether by reason of the ownership or leasing of
     property or the conduct of business, except where the failure so to qualify
     or to be in good standing would not result in a Material Adverse Effect;
     all of the issued and outstanding capital stock of each of the Subsidiaries
     that is a corporation has been duly authorized and validly issued, is fully
     paid and non-assessable, and all of the partnership interests in each
     Subsidiary that is a partnership are validly issued and fully paid; except
     as otherwise disclosed in the Registration Statement, all such shares and
     interests, as the case may be, are owned by the Company, directly or
     through Subsidiaries, free and clear of any security interest, mortgage,
     pledge, lien, encumbrance, claim or equity; none of the outstanding shares
     of capital stock or partnership interests of any Subsidiary was issued in
     violation of the preemptive or similar rights of any securityholder of such
     Subsidiary.

          (vii)  Good Standing of Property Partnerships.  Each of the Property
                 --------------------------------------                       
     Partnerships (as defined in the Registration Statement) has been duly
     organized and is validly existing as a general or limited partnership, in
     good standing (in the case of limited partnerships) under the laws of the
     jurisdiction of its organization, has partnership power and authority to
     own, lease and operate its properties, to conduct its business as described
     in the Prospectuses and to enter into and perform its respective
     obligations under the Formation Transaction Documents and is duly qualified
     as a foreign partnership to transact business and is in good standing in
     each jurisdiction in which such qualification is required, whether by
     reason of the ownership or leasing of property or the conduct of business,
     except where the failure so to qualify or to be in good standing would not
     result in a Material Adverse Effect; all of the partnership interests in
     each Property Partnership are validly issued and fully paid; none of the
     outstanding partnership interests of any Property Partnership was issued in
     violation of the preemptive or similar rights of any securityholder of such
     Property Partnership.

          (viii) Capitalization.  The authorized capital stock of the Company
                 --------------                                              
     is as set forth in the Prospectuses under the caption "Description of
     Capital Stock" and the issued and outstanding capital stock of the Company,
     as of the Closing Time, will be as set forth in the Prospectuses under the
     caption "Capitalization."  The shares of issued and outstanding capital
     stock of the Company have been duly authorized and validly issued and are
     fully paid and non-assessable; none of the outstanding shares of capital
     stock of

                                       7
<PAGE>
 
     the Company was issued in violation of the preemptive or other similar
     rights of any securityholder of the Company.

          (ix)  Authorization of Agreement.  This Agreement and the U.S.
                --------------------------                              
     Purchase Agreement have been duly authorized, executed and delivered by the
     Company and the Operating Partnership.

          (x)   Authorization and Description of Securities.  The Securities to
                -------------------------------------------                    
     be purchased by the International Managers and the U.S. Underwriters from
     the Company have been duly authorized for issuance and sale to the
     International Managers pursuant to this Agreement and the U.S. Underwriters
     pursuant to the U.S. Purchase Agreement, respectively, and, when issued and
     delivered by the Company pursuant to this Agreement and the U.S. Purchase
     Agreement, respectively, against payment of the consideration set forth
     herein and the U.S. Purchase Agreement, respectively, will be, as of the
     Closing Time, validly issued, fully paid and non-assessable; the Common
     Stock conforms, in all material respects, to all statements relating
     thereto contained in the Prospectuses and such description conforms, in all
     material respects, to the rights set forth in the instruments defining the
     same; no holder of the Securities will be subject to personal liability by
     reason of being such a holder; and the issuance of the Securities is not
     subject to the preemptive or other similar rights of any securityholder of
     the Company; the Company has duly reserved a sufficient number of shares of
     Common Stock for issuance upon exchange of outstanding OP Units in
     accordance with the Operating Partnership Agreement (as defined below).

          (xi)  Authorization of the Operating Partnership Agreement.  The
                ----------------------------------------------------      
     Amended and Restated Limited Partnership Agreement of the Operating
     Partnership (the "Operating Partnership Agreement") has been duly and
     validly authorized, executed and delivered by the parties thereto.

          (xii) Authorization and Description of OP Units.  The OP Units to be
                -----------------------------------------                     
     issued in connection with the Formation Transactions, including, without
     limitation, the OP Units to be issued to the Company, have been duly
     authorized for issuance by the Operating Partnership to the holders or
     prospective holders thereof, and at Closing Time will be validly issued,
     and fully paid and owned in the percentage amounts set forth in the
     Prospectuses by the Company and by the entities or persons described in the
     Prospectuses.  The OP Units have been and will be offered, issued and sold
     at or prior to Closing Time in compliance with all applicable laws
     (including, without limitation, federal and state securities laws).

          (xiii)  Absence of Defaults and Conflicts.  Neither the Company nor
                  ---------------------------------                          
     any of its Subsidiaries is in violation of its charter or by-laws or in
     default in the performance or observance of any obligation, agreement,
     covenant or condition contained in any contract, indenture, mortgage, deed
     of trust, loan or credit agreement, note, lease or other agreement or
     instrument to which the Company or any of its Subsidiaries is a party

                                       8
<PAGE>
 
     or by which it or any of them may be bound, or to which any of the property
     or assets of the Company or any Subsidiary is subject (collectively,
     "Agreements and Instruments") except for such defaults that would not
     result in a Material Adverse Effect; and the execution, delivery and
     performance of this Agreement and the U.S. Purchase Agreement and the
     consummation of the transactions contemplated in this Agreement, the U.S.
     Purchase Agreement and the Registration Statement (including the completion
     of the Formation Transactions, the issuance and sale of the Securities and
     the use of the proceeds from the sale of the Securities as described in the
     Prospectuses under the caption "Use of Proceeds") and compliance by the
     Company and the Operating Partnership with their obligations under this
     Agreement and the U.S. Purchase Agreement have been duly authorized by all
     necessary corporate or partnership action, as the case may be, and (except
     as contemplated by the Prospectuses) do not and will not, whether with or
     without the giving of notice or passage of time or both, conflict with or
     constitute a breach of, or default or Repayment Event (as defined below)
     under, or result in the creation or imposition of any lien, charge or
     encumbrance upon any property or assets of the Company or any Subsidiary
     pursuant to, the Agreements and Instruments or violations of any applicable
     law, statute, rule, regulation, judgment, order, writ or decree of any
     government, government instrumentality or court, domestic or foreign,
     having jurisdiction over the Company or any Subsidiary or any of their
     assets, properties or operations (except for such conflicts, breaches or
     defaults or liens, charges, encumbrances or violations that would not
     result in a Material Adverse Effect), nor will such action result in any
     violation of the provisions of the charter or by-laws of the Company or any
     Subsidiary.  As used herein, a "Repayment Event" means any event or
     condition which gives the holder of any note, debenture or other evidence
     of indebtedness (or any person acting on such holder's behalf) the right to
     require the repurchase, redemption or repayment of all or a portion of such
     indebtedness by the Company or any Subsidiary.

          Consummation of the Formation Transactions and compliance by the
     Company, its Subsidiaries and the Property Partnerships with their
     respective obligations under each of the documents relating thereto
     (collectively, the "Formation Transaction Documents") have been duly
     authorized by all necessary corporate or partnership action of such
     entities, as the case may be, and (except as contemplated by the
     Prospectuses) did not and will not violate or conflict with or constitute a
     breach of, or default under, or result in the creation or imposition of any
     lien, charge or encumbrance upon any of the Properties (as defined in the
     Registration Statement) or any other properties or assets of the Company or
     any of the Subsidiaries pursuant to any contract, indenture, mortgage, deed
     of trust, loan or credit agreement, note, lease or other agreement or
     instrument, including without limitation, any partnership agreement, to
     which the Company, any of the Subsidiaries or any Property Partnership is
     or was a party or by which it or any of them may be bound or affected, or
     to which any of the Properties or any other properties or assets of the
     Company or any of its Subsidiaries is subject (except for such violations,
     conflicts, breaches, defaults, liens, charges or encumbrances that would
     not result in a Material Adverse Effect); none of the Formation
     Transactions resulted or will result in

                                       9
<PAGE>
 
     the violation of any provisions of the charter, by-laws, partnership
     agreements or other governing document of the Company, any of the
     Subsidiaries or any Property Partnership (except in each case as may have
     been waived by all applicable parties), or any applicable law,
     administrative regulation or administrative or court decree (except for
     such violations of any applicable law, administrative regulation or
     administrative or court decree that would not result in a Material Adverse
     Effect); all authorizations, consents and approvals necessary to consummate
     the Formation Transactions were timely obtained; and the offer, issuance
     and exchange of the OP Units and general partnership interests in the
     Operating Partnership, the issuance and sale by the Company of Common Stock
     prior to the date hereof will be exempt from the registration requirements
     of the 1933 Act and applicable state securities laws.  At or prior to
     Closing Time, each of the Formation Transactions will have occurred, in all
     material respects, in the manner described in the Prospectuses.

          (xiv)  Authorization of the Formation Transaction Documents.  Each of
                 ----------------------------------------------------          
     the Formation Transaction Documents to which the Company, any of the
     Subsidiaries, any of the Property Partnerships or any affiliate of any such
     entity is a party has been duly authorized, executed and delivered by such
     party.

          (xv)   Absence of Labor Dispute.  No material labor dispute with the
                 ------------------------                                     
     employees of the Company or any Subsidiary exists or, to the knowledge of
     the Company, is imminent.

          (xvi)  Absence of Proceedings.  There is no action, suit, proceeding,
                 ----------------------                                        
     inquiry or investigation before or brought by any court or governmental
     agency or body, domestic or foreign, now pending, or, to the knowledge of
     the Company, threatened, against or affecting the Company or any
     Subsidiary, which is required to be disclosed in the Registration Statement
     (other than as disclosed therein), or which might reasonably be expected to
     result in a Material Adverse Effect, or which might reasonably be expected
     to materially and adversely affect the Properties or assets thereof or the
     consummation of the transactions contemplated in this Agreement, the U.S.
     Purchase Agreement and the Formation Transaction Documents or the
     performance by the parties of their obligations hereunder or thereunder;
     the aggregate of all pending legal or governmental proceedings to which the
     Company or any Subsidiary is a party or of which any of their respective
     property or assets, including without limitation the Properties, is the
     subject which are not described in the Registration Statement, including
     ordinary routine litigation incidental to the business, could not
     reasonably be expected to result in a Material Adverse Effect.

          (xvii)  Qualification as a REIT.  Commencing with the taxable year
                  -----------------------                                   
     ending December 31, 1997, the Company will be organized in conformity with
     the requirements for qualification as a real estate investment trust (a
     "REIT") under the Internal Revenue Code 1986, as amended (the "Code"), and
     its proposed method of operation will enable it to meet the requirements
     for taxation as a REIT under the Code.

                                       10
<PAGE>
 
          (xviii)   Accuracy of Exhibits. There are no contracts or documents
                    --------------------
     which are required to be described in the Registration Statement or the
     Prospectuses or to be filed as exhibits thereto which have not been so
     described and filed as required.

          (xix)     New York Stock Exchange Listing.  The Common Stock has been
                    -------------------------------                            
     approved for listing on the New York Stock Exchange, subject to an official
     notice of issuance.

          (xx)      Absence of Further Requirements.  No filing with, or
                    -------------------------------                     
     authorization, approval, consent, license, order, registration,
     qualification or decree of, any court or governmental authority or agency
     is necessary or required for the performance by the Company and the
     Operating Partnership of their obligations hereunder, in connection with
     the offering, issuance or sale of the Securities under this Agreement and
     the U.S. Purchase Agreement or the consummation of the transactions
     contemplated by this Agreement, the U.S. Purchase Agreement and the
     Formation Transaction Documents, except (i) such as have been already
     obtained or as may be required under the 1933 Act or the 1933 Act
     Regulations and foreign or state securities or blue sky laws, (ii) such as
     have been obtained under the laws and regulations of jurisdictions outside
     the United States in which the Reserved Securities are offered and (iii)
     state filings in connection with the Formation Transactions (which state
     filings will be made prior to or at the Closing Time).

          (xxi)     Possession of Licenses and Permits.  The Company and its
                    ----------------------------------                      
     Subsidiaries possess such permits, licenses, approvals, consents and other
     authorizations (collectively, "Governmental Licenses") issued by the
     appropriate federal, state, local or foreign regulatory agencies or bodies
     necessary to conduct the business now operated by them; the Company and its
     Subsidiaries are in compliance with the terms and conditions of all such
     Governmental Licenses, except where the failure so to comply would not,
     singly or in the aggregate, have a Material Adverse Effect; all of the
     Governmental Licenses are valid and in full force and effect, except when
     the invalidity of such Governmental Licenses or the failure of such
     Governmental Licenses to be in full force and effect would not have a
     Material Adverse Effect; and neither the Company nor any of its
     Subsidiaries has received any notice of proceedings relating to the
     revocation or modification of any such Governmental Licenses which, singly
     or in the aggregate, if the subject of an unfavorable decision, ruling or
     finding, would result in a Material Adverse Effect.

          (xxii)    The Properties.  (a)  Upon consummation of the Formation
                    --------------                                          
     Transactions, the Operating Partnership and the Subsidiaries will have good
     and marketable title in fee simple to all of the Properties and good and
     marketable title to all other real properties owned by them, in each case,
     free and clear of all mortgages, pledges, liens, security interests,
     claims, restrictions or encumbrances of any kind except such as (i) are
     described in the Prospectuses or (ii) do not, singly or in the aggregate,
     materially affect the value of such property and do not interfere with the
     use made and proposed to be made of such property by the Company or any of
     its Subsidiaries; (b) all mortgages,

                                       11
<PAGE>
 
     pledges, liens, security interests, claims, restrictions or encumbrances on
     or affecting the properties and assets (including without limitation the
     Properties) of the Company or any of the Subsidiaries that are required to
     be disclosed in the Prospectuses are disclosed therein; (c) neither the
     Company nor the Operating Partnership knows of any violation of any
     municipal, state or federal law, rule or regulation (including those
     pertaining to environmental matters) concerning the Properties or any part
     thereof which would, upon consummation of the Formation Transactions, have
     a Material Adverse Effect; (d) each of the Properties complies with all
     applicable zoning laws, ordinances, regulations and deed restrictions or
     other covenants in all material respects and, if and to the extent there is
     a failure to comply, such failure does not result in a Material Adverse
     Effect and will not result in a forfeiture or reversion of title; (e) none
     of the Company, any Subsidiary nor any Property Partnership has received
     from any governmental authority any written notice of any condemnation of
     or zoning change affecting the Properties or any part thereof, and none of
     the Company, any Subsidiary nor any Property Partnership knows of any such
     condemnation or zoning change which is threatened and which if consummated
     would have a Material Adverse Effect; and (f) no lessee of any portion of
     any of the Properties is in default under any of the leases governing such
     Properties and there is no event which, but for the passage of time or the
     giving of notice or both, would constitute a default under any of such
     leases, except such defaults that would not have a Material Adverse Effect.

          (xxiii)  Insurance.  Upon consummation of the Formation Transactions,
                   ---------                                                   
     the Company and each of the Subsidiaries will be insured by insurers of
     recognized financial responsibility against such losses and risks and in
     such amounts as are prudent and customary in the businesses in which they
     will be engaged; and neither the Company nor any of the Subsidiaries has
     any reason to believe that any of them will not be able to renew its
     existing insurance coverage as and when such coverage expires or to obtain
     similar coverage from similar insurers as may be necessary to continue its
     business.

          (xxiv)   Taxes. The Company and each of the Subsidiaries has filed all
                   -----
     material foreign, federal, state and local tax returns that are required to
     be filed or have requested extensions thereof (except in any case in which
     the failure so to file would not, upon consummation of the Formation
     Transactions, have a Material Adverse Effect) and has paid all taxes
     required to be paid by it and any other assessment, fine or penalty levied
     against it, to the extent that any of the foregoing is due and payable,
     except for any such assessment, fine or penalty that is currently being
     contested in good faith or as described in or contemplated by the
     Prospectuses.

          (xxv)     Mortgages and Deeds of Trust.  Except as set forth in the
                    ----------------------------                             
     Registration Statement and the Prospectuses, the mortgages and deeds of
     trust encumbering the properties and assets described in the Prospectus are
     not convertible and neither the Company, any of its Subsidiaries, any
     Property Partnership, nor any person affiliated therewith holds a
     participating interest therein, and such mortgages and deeds of trust are

                                       12
<PAGE>
 
     not cross-defaulted or cross-collateralized to any property not owned
     directly or indirectly by the Company or any of its Subsidiaries.

          (xxvi)    Compliance with Cuba Act. The Company has complied with, and
                    ------------------------
     is and will be in compliance with, the provisions of that certain Florida
     act relating to disclosure of doing business with Cuba, codified as Section
     517.075 of the Florida statutes, and the rules and regulations thereunder
     (collectively, the "Cuba Act") or is exempt therefrom.

          (xxvii)   Investment Company Act.  The Company and the Operating
                    ----------------------                                
     Partnership are not, and upon the issuance and sale of the Securities as
     herein contemplated and the application of the net proceeds therefrom as
     described in the Prospectuses will not be, an "investment company" as such
     term is defined in the Investment Company Act of 1940, as amended (the
     "1940 Act").

          (xxviii)  Environmental Laws.  Except as otherwise disclosed in the
                    ------------------                                       
     Prospectuses or in the Phase I Environmental Site Assessments and Asbestos
     Survey Reports previously delivered to the U.S. Representatives and
     International Managers or their counsel (the "Environmental Reports"), (i)
     the Company, its Subsidiaries and the Property Partnerships have been and
     are in compliance with applicable Environmental Statutes; (ii) neither the
     Company, any of the Subsidiaries, the Property Partnerships, nor, to the
     best knowledge of the Company, any other owners of the property at any time
     or any other party has at any time released (as such term is defined in
     Section 101(22) of CERCLA (as hereinafter defined)) or otherwise disposed
     of or dealt with, Hazardous Materials (as hereinafter defined) on, to or
     from the Properties, except for such releases as would not be reasonably
     likely to cause the Company to incur material liability that would require
     disclosure pursuant to federal or state laws regulating the issuance of
     securities; (iii) the Company does not intend to use the Properties or any
     subsequently acquired properties, other than in compliance with applicable
     Environmental Statutes (as hereinafter defined); (iv) neither the Company
     nor any of the Subsidiaries knows of any seepage, leak, discharge, release,
     emission, spill or dumping of Hazardous Materials into waters (including,
     but not limited, to groundwater and surface water) on, beneath or adjacent
     to the Properties or onto lands from which Hazardous Materials might seep,
     flow or drain into such waters; (v) neither the Company nor any of the
     Subsidiaries has received any notice of, or has any knowledge of any
     occurrence or circumstance which, with notice or passage of time or both,
     would give rise to a claim under or pursuant to any Environmental Statute
     or common law with respect to the Properties or the assets described in the
     Prospectus or arising out of the conduct of the Company, its Subsidiaries,
     or the Property Partnerships, except for such claims that would not be
     reasonably likely to cause the Company to incur material liability that
     would require disclosure pursuant to federal or state laws regulating the
     issuance of securities; (vi) neither the Properties nor any other land
     owned by the Company or any of the Subsidiaries is included or, to the best
     of the Company's knowledge, proposed for inclusion on the National
     Priorities List issued pursuant to CERCLA by the United States
     Environmental Protection Agency (the "EPA") or to the best of the Company's

                                       13
<PAGE>
 
     knowledge, proposed for inclusion on any similar list or inventory issued
     pursuant to any other Environmental Statute or issued by any other
     Governmental Authority (as hereinafter defined).

          As used herein, "Hazardous Material" shall include, without limitation
     any flammable explosives, radioactive materials, hazardous materials,
     hazardous wastes, toxic substances, or related materials, asbestos or any
     hazardous material as defined by any federal, state or local environmental
     law, ordinance, rule or regulation including, without limitation, the
     Comprehensive Environmental Response, Compensation, and Liability Act of
     1980, as amended, 42 U.S.C. (S)(S) 9601-9675 ("CERCLA"), the Hazardous
     Materials Transportation Act, as amended, 49 U.S.C. (S)(S) 1801-1819, the
     Resource Conservation and Recovery Act, as amended, 42 U.S.C. (S)(S) 6901-
     K, the Emergency Planning and Community Right-to-Know Act of 1986, 42
     U.S.C. (S)(S) 11001-11050, the Toxic Substances Control Act, 15 U.S.C.
     (S)(S) 2601-2671, the Federal Insecticide, Fungicide and Rodenticide Act, 7
     U.S.C. (S)(S) 136-136y, the Clean Air Act, 42 U.S.C. (S)(S) 7401-7642, the
     Clean Water Act (Federal Water Pollution Control Act), 33 U.S.C. (S)(S)
     1251-1387, the Safe Drinking Water Act, 42 U.S.C. (S)(S) 300f-300j-26, and
     the Occupational Safety and Health Act, 29 U.S.C. (S)(S) 651-678, as any of
     the above statutes may be amended from time to time, and in the regulations
     promulgated pursuant to each of the foregoing (including environmental
     statues not specifically defined herein) (individually, an "Environmental
     Statute" and collectively "Environmental Statutes") or by any federal,
     state or local governmental authority having or claiming jurisdiction over
     the properties and assets described in the Prospectus (a "Governmental
     Authority").

          (xxix)  Registration Rights.  Except as described in the Registration
                  -------------------                                          
     Statement, there are no persons with registration rights or other similar
     rights to have any securities registered pursuant to the Registration
     Statement or otherwise registered by the Company under the 1933 Act.

     (b) Officer's Certificates.  Any certificate signed by any officer of the
Company or any of its subsidiaries delivered to the Global Coordinators, the
Lead Managers or to counsel for the International Managers shall be deemed a
representation and warranty solely by the Company to each International Manager
as to the matters covered thereby.


     SECTION 2.  Sale and Delivery to International Managers; Closing.
                 ---------------------------------------------------- 

     (a) Initial Securities.  On the basis of the representations and warranties
herein contained and subject to the terms and conditions herein  set forth, the
Company agrees to sell to each International Manager, severally and not jointly,
and each International Manager, severally and not jointly, agrees to purchase
from the Company, at the price per share set forth in Schedule B, the number of
Initial International Securities set forth in Schedule A opposite the name of
such International Manager, plus any additional number of Initial International

                                       14
<PAGE>
 
Securities which such International Manager may become obligated to purchase
pursuant to the provisions of Section 10 hereof.

     (b) Option Securities.  In addition, on the basis of the representations
and warranties herein contained and subject to the terms and conditions herein
set forth, the Company hereby grants an option to the International Managers,
severally and not jointly, to purchase up to an additional 942,000 shares of
Common Stock at the price per share set forth in Schedule B, less an amount per
share equal to any dividends or distributions declared by the Company and
payable on the Initial International Securities but not payable on the
International Option Securities.  The option hereby granted will expire 30 days
after the date hereof and may be exercised in whole or in part from time to time
only for the purpose of covering over-allotments which may be made in connection
with the offering and distribution of the Initial International Securities upon
notice by the Global Coordinators to the Company setting forth the number of
International Option Securities as to which the several International Managers
are then exercising the option and the time and date of payment and delivery for
such International Option Securities.  Any such time and date of delivery for
the International Option Securities (a "Date of Delivery") shall be determined
by the Global Coordinators, but shall not be earlier than two nor later than
seven full business days after the exercise of said option, nor in any event
prior to the Closing Time, as hereinafter defined.  If the option is exercised
as to all or any portion of the International Option Securities, each of the
International Managers, acting severally and not jointly, will purchase that
proportion of the total number of International Option Securities then being
purchased which the number of Initial International Securities set forth in
Schedule A opposite the name of such International Manager bears to the total
number of Initial International Securities, subject in each case to such
adjustments as the Global Coordinators in their discretion shall make to
eliminate any sales or purchases of fractional shares.

     (c) Payment.  Payment of the purchase price for, and delivery of
certificates for, the Initial Securities shall be made at the offices of
Goodwin, Procter & Hoar LLP, Exchange Place, Boston, Massachusetts, or at such
other place as shall be agreed upon by the Global Coordinators and the Company,
at 9:00 A.M. (Eastern time) on the third (fourth, if the pricing occurs after
4:30 P.M. (Eastern time) on any given day) business day after the date hereof
(unless postponed in accordance with the provisions of Section 10), or such
other time not later than ten business days after such date as shall be agreed
upon by the Global Coordinators and the Company (such time and date of payment
and delivery being herein called "Closing Time").

     In addition, in the event that any or all of the International Option
Securities are purchased by the International Managers, payment of the purchase
price for, and delivery of certificates for, such International Option
Securities shall be made at the above-mentioned offices, or at such other place
as shall be agreed upon by the Global Coordinators and the Company, on each Date
of Delivery as specified in the notice from the Global Coordinators to the
Company.

     Payment shall be made to the Company by wire transfer of immediately
available funds to a bank account designated by the Company, against delivery to
the Lead Managers for the

                                       15
<PAGE>
 
respective accounts of the International Managers of certificates for the
International Securities to be purchased by them.  It is understood that each
International Manager has authorized the Lead Managers, for its account, to
accept delivery of, receipt for, and make payment of the purchase price for, the
Initial International Securities and the International Option Securities, if
any, which it has agreed to purchase.  Merrill Lynch (Int'l) or Goldman Sachs
(Int'l), individually and not as representatives of the International Managers,
may (but shall not be obligated to) make payment of the purchase price for the
Initial International Securities or the International Option Securities, if any,
to be purchased by any International Manager whose funds have not been received
by the Closing Time or the relevant Date of Delivery, as the case may be, but
such payment shall not relieve such International Manager from its obligations
hereunder.

     (d) Denominations; Registration.  Certificates for the Initial
International Securities and the International Option Securities, if any, shall
be in such denominations and registered in such names as the Lead Managers may
request in writing at least one full business day before the Closing Time or the
relevant Date of Delivery, as the case may be.  The certificates for the Initial
International Securities and the International Option Securities, if any, will
be made available for examination and packaging by the Lead Managers in The City
of New York not later than 10:00 A.M. (Eastern time) on the business day prior
to the Closing Time or the relevant Date of Delivery, as the case may be.

     SECTION 3.  Covenants of the Company.  Each of the Company and the
                 ------------------------                              
Operating Partnership covenants with each International Manager as follows:

          (a) Compliance with Securities Regulations and Commission Requests.
     The Company, subject to Section 3(b), will comply with the requirements of
     Rule 430A or Rule 434, as applicable, and will notify the Global
     Coordinators promptly, and confirm the notice in writing, (i) when any
     post-effective amendment to the Registration Statement shall become
     effective, or any supplement to the Prospectuses or any amended
     Prospectuses shall have been filed, (ii) of the receipt of any comments
     from the Commission, (iii) of any request by the Commission for any
     amendment to the Registration Statement or any amendment or supplement to
     the Prospectuses or for additional information, and (iv) of the issuance by
     the Commission of any stop order suspending the effectiveness of the
     Registration Statement or of any order preventing or suspending the use of
     any preliminary prospectus, or of the suspension of the qualification of
     the Securities for offering or sale in any jurisdiction, or of the
     initiation or threatening of any proceedings for any of such purposes.  The
     Company will promptly effect the filings necessary pursuant to Rule 424(b)
     and will take such steps as it deems necessary to ascertain promptly
     whether the form of prospectus transmitted for filing under Rule 424(b) was
     received for filing by the Commission and, in the event that it was not, it
     will promptly file such prospectus.  The Company will make every reasonable
     effort to prevent the issuance of any stop order and, if any stop order is
     issued, to obtain the lifting thereof at the earliest possible moment.

                                       16
<PAGE>
 
          (b) Filing of Amendments.  The Company will give the Global
     Coordinators notice of its intention to file or prepare any amendment to
     the Registration Statement (including any filing under Rule 462(b)), any
     Term Sheet or any amendment, supplement or revision to either the
     prospectus included in the Registration Statement at the time it became
     effective or to the Prospectuses, will furnish the Global Coordinators with
     copies of any such documents a reasonable amount of time prior to such
     proposed filing or use, as the case may be, and will not file or use any
     such document to which the Global Coordinators or counsel for the
     International Managers shall reasonably object.

          (c) Delivery of Registration Statements.  The Company has furnished
     or, upon request, will deliver to the Lead Managers and counsel for the
     International Managers, without charge, signed copies of the Registration
     Statement as originally filed and of each amendment thereto (including
     exhibits filed therewith or incorporated by reference therein) and signed
     copies of all consents and certificates of experts, and will also deliver
     to the Lead Managers, without charge, a conformed copy of the Registration
     Statement as originally filed and of each amendment thereto (without
     exhibits) for each of the International Managers.  The copies of the
     Registration Statement and each amendment thereto furnished to the
     International Managers will be identical to the electronically transmitted
     copies thereof filed with the Commission pursuant to EDGAR, except to the
     extent permitted or required by Regulation S-T.

          (d) Delivery of Prospectuses.  The Company has delivered to each
     International Manager, without charge, as many copies of each preliminary
     prospectus as such International Manager reasonably requested, and the
     Company hereby consents to the use of such copies for purposes permitted by
     the 1933 Act in connection with the offering of the Securities.  The
     Company will furnish to each International Manager, without charge, during
     the period when the International Prospectus is required to be delivered
     under the 1933 Act or the Securities Exchange Act of 1934 (the "1934 Act"),
     such number of copies of the International Prospectus (as amended or
     supplemented) as such International Manager may reasonably request.  The
     International Prospectus and any amendments or supplements thereto
     furnished to the International Managers will be identical to the
     electronically transmitted copies thereof filed with the Commission
     pursuant to EDGAR, except to the extent permitted or required by Regulation
     S-T.

          (e) Continued Compliance with Securities Laws.  The Company will
     comply with the 1933 Act and the 1933 Act Regulations so as to permit the
     completion of the distribution of the Securities as contemplated in this
     Agreement, the U.S. Purchase Agreement and in the Prospectuses.  If at any
     time when a prospectus is required by the 1933 Act to be delivered in
     connection with sales of the Securities, any event shall occur or condition
     shall exist as a result of which it is necessary, in the reasonable opinion
     of counsel for the International Managers or for the Company, to amend the
     Registration Statement or amend or supplement any Prospectus in order that
     the Prospectuses will not include any untrue statements of a material fact
     or omit to state a material fact necessary in order to make the statements
     therein not misleading in the light of the circumstances

                                       17
<PAGE>
 
     existing at the time it is delivered to a purchaser, or if it shall be
     necessary, in the reasonable opinion of such counsel, at any such time to
     amend the Registration Statement or amend or supplement any Prospectus in
     order to comply with the requirements of the 1933 Act or the 1933 Act
     Regulations, the Company will promptly prepare and file with the
     Commission, subject to Section 3(b), such amendment or supplement as may be
     necessary to correct such statement or omission or to make the Registration
     Statement or the Prospectuses comply with such requirements, and the
     Company will furnish to the International Managers such number of copies of
     such amendment or supplement as the International Managers may reasonably
     request.

          (f) Blue Sky Qualifications.  The Company will use its best efforts,
     in cooperation with the International Managers, to qualify, if necessary,
     the Securities for offering and sale under the applicable securities laws
     of such states and other jurisdictions (domestic or foreign) as the Global
     Coordinators may designate and to maintain such qualifications in effect
     for a period of not more than one year from the later of the effective date
     of the Registration Statement and any Rule 462(b) Registration Statement;
     provided, however, that the Company shall not be obligated to file any
     general consent to service of process or to qualify as a foreign
     corporation or as a dealer in securities in any jurisdiction in which it is
     not so qualified or to subject itself to taxation in respect of doing
     business in any jurisdiction in which it is not otherwise so subject.  In
     each jurisdiction in which the Securities have been so qualified, the
     Company will file such statements and reports as may be required by the
     laws of such jurisdiction to continue such qualification in effect for a
     period of not more than one year from the effective date of the
     Registration Statement and any Rule 462(b) Registration Statement.

          (g) Rule 158.  The Company will timely file such reports pursuant to
     the 1934 Act as are necessary in order to make generally available to its
     securityholders as soon as practicable an earnings statement for the
     purposes of, and to provide the benefits contemplated by, the last
     paragraph of Section 11(a) of the 1933 Act.

          (h) Use of Proceeds.  The Company will use the net proceeds received
     by it from the sale of the Securities in the manner specified in the
     Prospectuses under "Use of Proceeds".

          (i) Listing.  The Company will use its best efforts to effect the
     listing of the Common Stock (including the Securities) on the New York
     Stock Exchange.

          (j) Restriction on Sale of Securities.  During a period of one year
     from the date of the Prospectuses, the Company and the Operating
     Partnership will not, without the prior written consent of the Global
     Coordinators, (i) directly or indirectly, offer, pledge, sell, contract to
     sell, sell any option or contract to purchase, purchase any option or
     contract to sell, grant any option, right or warrant to purchase or
     otherwise transfer or dispose of any share of Common Stock or OP Units or
     any securities convertible into or exercisable or exchangeable for Common
     Stock or OP Units, or file any registration

                                       18
<PAGE>
 
     statement under the 1933 Act with respect to any of the foregoing or (ii)
     enter into any swap or any other agreement or any transaction that
     transfers, in whole or in part, directly or indirectly, the economic
     consequence of ownership of the Common Stock, whether any such swap or
     transaction described in clause (i) or (ii) above is to be settled by
     delivery of Common Stock or such other securities, in cash or otherwise.
     The foregoing sentence shall not apply to (A) the Securities to be sold
     hereunder or under the U.S. Purchase Agreement or (B) any shares of Common
     Stock issued or options to purchase Common Stock granted pursuant to
     existing employee benefit plans of the Company referred to in the
     Prospectuses or any employee benefit plans of the Company which have been
     approved by the requisite vote of the stockholders of the Company at a duly
     called meeting of stockholders.

          (k) Lock-up Agreements.  The Company will use its best efforts to
     cause each holder of Common Stock or OP Units issued in connection with the
     Formation Transactions to enter into a written agreement, in form and
     substance satisfactory to Merrill Lynch (Int'l) and Goldman Sachs (Int'l),
     on behalf of the Underwriters, to the effect set forth in Exhibit A hereto.

          (l) Qualification as a REIT.  The Company will use its best efforts to
     meet the requirements to qualify, for the taxable year ending December 31,
     1997, as a REIT under the Code.

          (m) Compliance with NASD Rules.  The Company hereby agrees that it
     will ensure that the Reserved Securities will be restricted as required by
     the National Association of Securities Dealers, Inc. (the "NASD") or the
     NASD rules from sale, transfer, assignment, pledge or hypothecation for a
     period of three months following the date of this Agreement.  The
     Underwriters will notify the Company as to which persons will need to be so
     restricted.  At the request of the Underwriters, the Company will direct
     the transfer agent to place a stop transfer restriction upon such
     securities for such period of time.  Should the Company release, or seek to
     release, from such restrictions any of the Reserved Securities, the Company
     agrees to reimburse the Underwriters for any reasonable expenses
     (including, without limitation, legal expenses) they incur in connection
     with such release.

          (n) Compliance with Rule 463.  The Company will file with the
     Commission such reports on Form SR as may be required pursuant to Rule 463
     of the 1933 Act Regulations.

     SECTION 4.  Payment of Expenses.  (a)  Expenses.  The Company will pay all
                 -------------------                                           
expenses incident to the performance of its obligations under this Agreement,
including (i) the preparation, printing and filing of the Registration Statement
(including financial statements and exhibits) as originally filed and of each
amendment thereto, (ii) the preparation, printing and delivery to the
Underwriters of this Agreement, any Agreement among Underwriters and such other
documents as may be required in connection with the offering, purchase, sale,
issuance or delivery of the

                                       19
<PAGE>
 
Securities, (iii) the preparation, issuance and delivery of the certificates for
the Securities to the Underwriters, including any stock or other transfer taxes
and any stamp or other duties payable upon the sale, issuance or delivery of the
Securities to the Underwriters and the transfer of the Securities between the
U.S. Underwriters and the International Managers, (iv) the fees and
disbursements of the Company's counsel, accountants and other advisors, (v) the
qualification or registration (or exemption therefrom) of the Securities under
securities laws in accordance with the provisions of Section 3(f) hereof,
including filing fees and the reasonable fees and disbursements of counsel for
the Underwriters in connection therewith and in connection with the preparation
of the Blue Sky Survey and any supplement thereto, (vi) the printing and
delivery to the Underwriters of copies of each preliminary prospectus, any Term
Sheets and of the Prospectuses and any amendments or supplements thereto, (vii)
the preparation, printing and delivery to the Underwriters of copies of the Blue
Sky Survey and any supplement thereto, (viii) the fees and expenses of any
transfer agent or registrar for the Securities and (ix) the filing fees incident
to, and the reasonable fees and disbursements of counsel to the Underwriters in
connection with, the review by the NASD of the terms of the sale of the
Securities, (x) the fees and expenses incurred in connection with the listing of
the Securities on the New York Stock Exchange and (xi) all costs and expenses of
the Underwriters, including the fees and disbursements of counsel for the
Underwriters, in connection with matters related to the Reserved Securities
which are designated by the Company for sale to employees and others having a
business relationship with the Company.

     (b)  Termination of Agreement.  If this Agreement is terminated by the Lead
Managers in accordance with the provisions of Section 5 or Section 9(a)(i)
hereof, the Company shall reimburse the International Managers for all of their
out-of-pocket expenses, including the reasonable fees and disbursements of
counsel for the International Managers.

     SECTION 5.  Conditions of International Managers' Obligations.  The
                 -------------------------------------------------      
obligations of the several International Managers hereunder are subject to the
accuracy of the representations and warranties of the Company contained in
Section 1 hereof or in certificates of any officer of the Company or any
subsidiary of the Company delivered pursuant to the provisions hereof, to the
performance by the Company of its covenants and other obligations hereunder, and
to the following further conditions:

          (a) Effectiveness of Registration Statement.  The Registration
     Statement, including any Rule 462(b) Registration Statement, has become
     effective and at Closing Time no stop order suspending the effectiveness of
     the Registration Statement shall have been issued under the 1933 Act or
     proceedings therefor initiated or threatened by the Commission, and any
     request on the part of the Commission for additional information shall have
     been complied with to the reasonable satisfaction of counsel to the
     International Managers.  A prospectus containing the Rule 430A Information
     shall have been filed with the Commission in accordance with Rule 424(b)
     (or a post-effective amendment providing such information shall have been
     filed and declared effective in accordance with the requirements of Rule
     430A) or, if the Company has elected to rely

                                       20
<PAGE>
 
     upon Rule 434, a Term Sheet shall have been filed with the Commission in
     accordance with Rule 424(b).

          (b) Opinion of Counsel for Company.  At Closing Time, the Lead
     Managers shall have received the favorable opinion, dated as of Closing
     Time, of Goodwin, Procter & Hoar LLP, counsel for the Company and the
     Operating Partnership, in form and substance satisfactory to counsel for
     the International Managers, together with signed or reproduced copies of
     such letter for each of the other International Managers to the effect set
     forth in Exhibit B hereto and to such further effect as counsel to the
     International Managers may reasonably request.

          (c) Opinion of General Counsel of Company.  At Closing Time, the Lead
     Managers shall have received the favorable opinion, dated as of Closing
     Time, of Frederick J. DeAngelis, General Counsel of the Company, in form
     and substance satisfactory to counsel for the International Managers,
     together with signed or reproduced copies of such letter for each of the
     other International Managers, to the effect set forth in Exhibit B hereto
     and to such further effect as counsel to the International Managers may
     reasonably request.

          (d) Opinion of Counsel for International Managers.  At Closing Time,
     the Lead Managers shall have received the favorable opinion, dated as of
     Closing Time, of Skadden, Arps, Slate, Meagher & Flom LLP, counsel for the
     International Managers, together with signed or reproduced copies of such
     letter for each of the other International Managers with respect to the
     matters set forth in clauses (i), (x), (xi), (solely as to preemptive or
     other similar rights arising by operation of law or under the charter or
     by-laws of the Company), (xiv) through (xvi), inclusive, and the
     penultimate paragraph of Exhibit B hereto.

     In giving the opinions described in paragraphs (b), (c) and (d) above, each
counsel may rely, as to all matters governed by the laws of jurisdictions other
than the law of the State of New York, the Commonwealth of Massachusetts, the
federal law of the United States and the General Corporation Law of the State of
Delaware, upon the opinions of counsel satisfactory to the Lead Managers.  Such
counsel may also state that, insofar as such opinion involves factual matters,
they have relied, to the extent they deem proper, upon certificates of officers
of the Company and its Subsidiaries and certificates of public officials.

          (e) Officers' Certificate.  At Closing Time, there shall not have
     been, since the date hereof or since the respective dates as of which
     information is given in the Prospectuses, any material adverse change in
     the condition, financial or otherwise, or in the earnings, business affairs
     or business prospects of the Company, the Operating Partnership and the
     Subsidiaries considered as one enterprise, whether or not arising in the
     ordinary course of business, and the Lead Managers shall have received a
     certificate of the President or a Vice President of the Company and of the
     chief financial or chief accounting officer of the Company and appropriate
     officers of the Company, as General

                                       21

<PAGE>
 
     Partner, on behalf of the Operating Partnership, dated as of Closing Time,
     to the effect that (i) there has been no such material adverse change, (ii)
     the representations and warranties in Section 1(a) hereof are true and
     correct in all material respects with the same force and effect as though
     expressly made at and as of Closing Time, (iii) the Company has complied in
     all material respects with all agreements and satisfied all conditions on
     its part to be performed or satisfied at or prior to Closing Time, and (iv)
     no stop order suspending the effectiveness of the Registration Statement
     has been issued and no proceedings for that purpose have been instituted or
     are pending or are contemplated by the Commission.

          (f) Accountant's Comfort Letter.  At the time of the execution of this
     Agreement, the Lead Managers shall have received from Coopers & Lybrand
     L.L.P. a letter dated such date, in form and substance satisfactory to the
     Lead Managers, together with signed or reproduced copies of such letter for
     each of the other International Managers containing statements and
     information of the type ordinarily included in accountants' "comfort
     letters" to underwriters with respect to the financial statements and
     certain financial information contained in the Registration Statement and
     the Prospectuses.

          (g) Bring-down Comfort Letter.  At Closing Time, the Lead Managers
     shall have received from Coopers & Lybrand L.L.P. a letter, dated as of
     Closing Time, to the effect that they reaffirm the statements made in the
     letter furnished pursuant to subsection (f) of this Section, except that
     the specified date referred to shall be a date not more than three business
     days prior to Closing Time.

          (h) Approval of Listing.  At Closing Time, the Securities shall have
     been approved for listing on the New York Stock Exchange, subject only to
     official notice of issuance.

          (i) No Objection.  The NASD has confirmed that it has not raised any
     objection with respect to the fairness and reasonableness of the
     underwriting terms and arrangements.

          (j) Lock-up Agreements.  At the date of this Agreement, the Lead
     Managers shall have received the agreements described in Section 3(k)
     hereof.

          (k) Purchase of Initial U.S. Securities.  Contemporaneously with the
     purchase by the International Managers of the Initial International
     Securities under this Agreement, the U.S. Underwriters shall have purchased
     the Initial U.S. Securities under the U.S. Purchase Agreement.

          (l) Conditions to Purchase of International Option Securities.  In the
     event that the International Managers exercise their option provided in
     Section 2(b) hereof to purchase all or any portion of the International
     Option Securities, the representations and

                                       22
<PAGE>
 
     warranties of the Company contained herein and the statements in any
     certificates furnished by the Company or any subsidiary of the Company
     hereunder shall be true and correct as of each Date of Delivery and, at the
     relevant Date of Delivery, the Lead Managers shall have received:

          (i)    Officers' Certificate.  A certificate, dated such Date of
                 ---------------------                                    
          Delivery, of the President or a Vice President of the Company and of
          the chief financial or chief accounting officer of the Company
          confirming that the certificate delivered at the Closing Time pursuant
          to Section 5(e) hereof remains true and correct as of such Date of
          Delivery.

          (ii)   Opinion of Counsel for Company.  The favorable opinion of
                 ------------------------------                           
          Goodwin, Procter & Hoar LLP, counsel for the Company and the Operating
          Partnership, in form and substance satisfactory to counsel for the
          International Managers, dated such Date of Delivery, relating to the
          International Option Securities to be purchased on such Date of
          Delivery and otherwise to the same effect as the opinion required by
          Section 5(b) hereof.

          (iii)  Opinion of General Counsel for Company.  The favorable opinion
                 --------------------------------------                        
          of of Frederick J. DeAngelis, General Counsel of the Company, in form
          and substance satisfactory to counsel for the International Managers,
          dated such Date of Delivery, relating to the International Option
          Securities to be purchased on such Date of Delivery and otherwise to
          the same effect as the opinion required by Section 5(c) hereof.

          (iv)   Opinion of Counsel for International Managers.  The favorable
                 ---------------------------------------------                
          opinion of Skadden, Arps, Slate, Meagher & Flom LLP, counsel for the
          International Managers, dated such Date of Delivery, relating to the
          International Option Securities to be purchased on such Date of
          Delivery and otherwise to the same effect as the opinion required by
          Section 5(d) hereof.

          (v)    Bring-down Comfort Letter.  A letter from Coopers & Lybrand
                 -------------------------                                  
          L.L.P., in form and substance satisfactory to the Lead Managers and
          dated such Date of Delivery, substantially in the same form and
          substance as the letter furnished to the Lead Managers pursuant to
          Section 5(g) hereof, except that the "specified date" in the letter
          furnished pursuant to this paragraph shall be a date not more than
          five days prior to such Date of Delivery.

     (m) Additional Documents.  At Closing Time and at each Date of Delivery,
counsel for the International Managers shall have been furnished with such
documents and opinions as they may reasonably require for the purpose of
enabling them to pass upon the issuance and sale of the Securities as herein
contemplated, or in order to evidence the accuracy of any of the representations
or warranties, or the fulfillment of any of the conditions, herein contained;
and all proceedings taken by the Company in connection with the issuance and
sale of the Securities

                                       23
<PAGE>
 
as herein contemplated shall be reasonably satisfactory in form and substance to
the Lead Managers and counsel for the International Managers.

     (n) Termination of Agreement.  If any condition specified in this Section
shall not have been fulfilled when and as required to be fulfilled, this
Agreement, or, in the case of any condition to the purchase of International
Option Securities on a Date of Delivery which is after the Closing Time, the
obligations of the several International Managers to purchase the relevant
Option Securities may be terminated by the Lead Managers by notice to the
Company at any time at or prior to Closing Time or such Date of Delivery, as the
case may be, and such  termination shall be without liability of any party to
any other party except as provided in Section 4 and except that Sections 1, 6, 7
and 8 shall survive any such termination and remain in full force and effect.

     SECTION 6.  Indemnification.
                 --------------- 

     (a) Indemnification of International Managers.  The Company and the
Operating Partnership jointly agree to indemnify and hold harmless each
International Manager and each person, if any, who controls any International
Manager within the meaning of Section 15 of the 1933 Act or Section 20 of the
1934 Act as follows:

          (i)   against any and all loss, liability, claim, damage and expense
     whatsoever, as incurred, arising out of any untrue statement or alleged
     untrue statement of a material fact contained in the Registration Statement
     (or any amendment thereto), including the Rule 430A Information and the
     Rule 434 Information, if applicable, or the omission or alleged omission
     therefrom of a material fact required to be stated therein or necessary to
     make the statements therein not misleading or arising out of any untrue
     statement or alleged untrue statement of a material fact included in any
     preliminary prospectus or the Prospectuses (or any amendment or supplement
     thereto), or the omission or alleged omission therefrom of a material fact
     necessary in order to make the statements therein, in the light of the
     circumstances under which they were made, not misleading;

          (ii)  against any and all loss, liability, claim, damage and expense
     whatsoever, as incurred, arising out of (A) the violation of any applicable
     laws or regulations of foreign jurisdictions where Reserved Securities have
     been offered and (B) any untrue statement or alleged untrue statement of a
     material fact included in the supplement or prospectus wrapper material
     distributed in [Canada] in connection with the reservation and sale of the
     Reserved Securities to eligible employees and persons having business
     relationships with the Company or the omission or alleged omission
     therefrom of a material fact necessary to make the statements therein, when
     considered in conjunction with the Prospectuses or preliminary
     prospectuses, not misleading;

          (iii) against any and all loss, liability, claim, damage and expense
     whatsoever, as incurred, to the extent of the aggregate amount paid in
     settlement of any litigation, or any investigation or proceeding by any
     governmental agency or body, commenced or

                                       24
<PAGE>
 
     threatened, or of any claim whatsoever based upon any such untrue statement
     or omission, or any such alleged untrue statement or omission or in
     connection with any violation of the nature referred to in Section
     6(a)(ii)(A) hereof; provided that (subject to Section 6(d) below) any such
     settlement is effected with the written consent of the Company; and

          (iv) against any and all expense whatsoever, as incurred (including
     the fees and disbursements of counsel chosen by Merrill Lynch (Int'l) and
     Goldman Sachs (Int'l)), reasonably incurred in investigating, preparing or
     defending against any litigation, or any investigation or proceeding by any
     governmental agency or body, commenced or threatened, or any claim
     whatsoever based upon any such untrue statement or omission, or any such
     alleged untrue statement or omission or in connection with any violation of
     the nature referred to in Section 6(a)(ii)(A) hereof, to the extent that
     any such expense is not paid under (i) or (ii) or (ii) above;

provided, however, that this indemnity agreement shall not apply to any loss,
- --------  -------                                                            
liability, claim, damage or expense to the extent arising out of (A) any untrue
statement or omission or alleged untrue statement or omission made in reliance
upon and in conformity with written information furnished to the Company and the
Operating Partnership by any International Manager through the Lead Managers
expressly for use in the Registration Statement (or any amendment thereto),
including the Rule 430A Information and the Rule 434 Information, if applicable,
or any preliminary prospectus or the International Prospectus (or any amendment
or supplement thereto) or (B) the fact that such International Manager sold
Securities to a person as to whom it shall be established that there was not
sent or given, at or prior to the written confirmation of such sale, a copy of
the International Prospectus or of the International Prospectus as then amended
or supplemented in any case where such delivery is required by the 1933 Act if
the Company has previously furnished copies thereof in sufficient quantity to
such International Manager and the loss, claim, damage or liability of such
International Manager results from an untrue statement or omission of a material
fact contained in any preliminary prospectus or International Prospectus (or any
amendment or supplement thereto), which was corrected in the International
Prospectus or in the International Prospectus as then amended or supplemented,
and delivery would have cured the defect giving rise to such loss, claim, damage
or liability.

     (b) Indemnification of Company, Directors and Officers.  Each International
Manager severally agrees to indemnify and hold harmless the Company, its
directors, each of its officers who signed the Registration Statement, and each
person, if any, who controls the Company within the meaning of Section 15 of the
1933 Act or Section 20 of the 1934 Act against any and all loss, liability,
claim, damage and expense described in the indemnity contained in subsection (a)
of this Section, as incurred, but only with respect to untrue statements or
omissions, or alleged untrue statements or omissions, made in the Registration
Statement (or any amendment thereto), including the Rule 430A Information and
the Rule 434 Information, if applicable, or any preliminary international
prospectus or the International Prospectus (or any amendment or supplement
thereto) in reliance upon and in conformity with written information furnished
to the Company by such International Manager through the Lead Managers expressly

                                       25
<PAGE>
 
for use in the Registration Statement (or any amendment thereto) or such
preliminary prospectus or the International Prospectus (or any amendment or
supplement thereto).  The Company and the Operating Partnership acknowledge that
the statements set forth in the last paragraph of the cover page and in the
second, fifth and twelfth through fifteenth paragraphs under the caption
"Underwriting" in the Prospectus constitute the only information furnished in
writing by or on behalf of any Underwriter expressly for use in the Registration
Statement relating to the Securities as originally filed or in any amendment
thereof, a related preliminary prospectus or the Prospectuses or in any
amendment thereof or supplement thereto, as the case may be.

     (c) Actions against Parties; Notification.  Each indemnified party shall
give notice as promptly as reasonably practicable to each indemnifying party of
any action commenced against it in respect of which indemnity may be sought
hereunder, but failure to so notify an indemnifying party shall not relieve such
indemnifying party from any liability hereunder to the extent it is not
materially prejudiced as a result thereof and in any event shall not relieve it
from any liability which it may have otherwise than on account of this indemnity
agreement.  In the case of parties indemnified pursuant to Section 6(a) above,
counsel to the indemnified parties shall be selected by Merrill Lynch (Int'l)
and Goldman Sachs (Int'l), and, in the case of parties indemnified pursuant to
Section 6(b) above, counsel to the indemnified parties shall be selected by the
Company.  An indemnifying party may participate at its own expense in the
defense of any such action; provided, however, that counsel to the indemnifying
party shall not (except with the consent of the indemnified party) also be
counsel to the indemnified party.  Notwithstanding the foregoing, if it so
elects within a reasonable time after receipt of such notice, an indemnifying
party, jointly with any other indemnifying parties receiving such notice, may
assume the defense of such action with counsel chosen by it and approved by the
indemnified parties defendant in such action (which approval shall not be
unreasonably withheld), unless such indemnified parties reasonably object to
such assumption on the ground that there may be legal defenses available to them
which are different from or in addition to those available to such indemnifying
party.  If an indemnifying party assumes the defense of such action, the
indemnifying party shall not be liable for any fees and expenses of counsel for
the indemnified parties incurred thereafter in connection with such action,
except the indemnifying party shall be liable for the reasonable costs of
investigation subsequently incurred by the indemnified party in connection with
the defense.  In no event shall the indemnifying parties be liable for fees and
expenses of more than one counsel (in addition to any local counsel) separate
from their own counsel for all indemnified parties in connection with any one
action or separate but similar or related actions in the same jurisdiction
arising out of the same general allegations or circumstances.  No indemnifying
party shall, without the prior written consent of the indemnified parties, which
consent shall not be unreasonably withheld, settle or compromise or consent to
the entry of any judgment with respect to any litigation, or any investigation
or proceeding by any governmental agency or body, commenced or threatened, or
any claim whatsoever in respect of which indemnification or contribution could
be sought under this Section 6 or Section 7 hereof (whether or not the
indemnified parties are actual or potential parties thereto), unless such
settlement, compromise or consent (i) includes an unconditional release of each
indemnified party from all liability arising out of such litigation,
investigation, proceeding or claim and (ii)

                                       26
<PAGE>
 
does not include a statement as to or an admission of fault, culpability or a
failure to act by or on behalf of any indemnified party.

     (d) Settlement without Consent if Failure to Reimburse.  If at any time an
indemnified party shall have requested an indemnifying party to reimburse the
indemnified party for fees and expenses of counsel, such indemnifying party
agrees that it shall be liable for any settlement of the nature contemplated by
Section 6(a)(i)(iii) effected without its written consent if (i) such settlement
is entered into more than 45 days after receipt by such indemnifying party of
the aforesaid request, (ii) such indemnifying party shall have received notice
of the terms of such settlement at least 30 days prior to such settlement being
entered into and (iii) such indemnifying party shall not have reimbursed such
indemnified party in accordance with such request prior to the date of such
settlement.

     (e) Indemnification for Reserved Securities.  In connection with the offer
and sale of the Reserved Securities, the Company agrees, promptly upon a request
in writing, to indemnify and hold harmless the Underwriters from and against any
and all losses, liabilities, claims, damages and expenses incurred by them as a
result of the failure of eligible employees and persons having business
relationships with the Company to pay for and accept delivery of Reserved
Securities which, by the end of the first business day following the date of
this Agreement, were subject to a properly confirmed agreement to purchase.

     SECTION 7.  Contribution.  If the indemnification provided for in Section 6
                 ------------                                                   
hereof is for any reason unavailable to or insufficient to hold harmless an
indemnified party in respect of any losses, liabilities, claims, damages or
expenses referred to therein, then each indemnifying party shall contribute to
the aggregate amount of such losses, liabilities, claims, damages and expenses
incurred by such indemnified party, as incurred, (i) in such proportion as is
appropriate to reflect the relative benefits received by the Company and the
Operating Partnership on the one hand and the International Managers on the
other hand from the offering of the Securities pursuant to this Agreement or
(ii) if the allocation provided by clause (i) is not permitted by applicable
law, in such proportion as is appropriate to reflect not only the relative
benefits referred to in clause (i) above but also the relative fault of the
Company and the Operating Partnership on the one hand and of the International
Managers on the other hand in connection with the statements or omissions, or in
connection with any violation of the nature referred to in Section 6(a)(ii)(A)
hereof, which resulted in such losses, liabilities, claims, damages or expenses,
as well as any other relevant equitable considerations.

     The relative benefits received by the Company and the Operating Partnership
on the one hand and the International Managers on the other hand in connection
with the offering of the International Securities pursuant to this Agreement
shall be deemed to be in the same respective proportions as the total net
proceeds from the offering of the International Securities pursuant to this
Agreement (before deducting expenses) received by the Company and the Operating
Partnership and the total underwriting discount received by the International
Managers, in each case as set forth on the cover of the International
Prospectus, or, if Rule 434 is used, the

                                       27
<PAGE>
 
corresponding location on the Term Sheet, bear to the aggregate initial public
offering price of the International Securities as set forth on such cover.

     The relative fault of the Company and the Operating Partnership on the one
hand and the International Managers on the other hand shall be determined by
reference to, among other things, whether any such untrue or alleged untrue
statement of a material fact or omission or alleged omission to state a material
fact relates to information supplied by the Company, the Operating Partnership
or by the International Managers and the parties' relative intent, knowledge,
access to information and opportunity to correct or prevent such statement or
omission or any violation of the nature referred to in Section 6(a)(ii)(A)
hereof.

     The Company, the Operating Partnership and the International Managers agree
that it would not be just and equitable if contribution pursuant to this Section
7 were determined by pro rata allocation (even if the International Managers
were treated as one entity for such purpose) or by any other method of
allocation which does not take account of the equitable considerations referred
to above in this Section 7.  The aggregate amount of losses, liabilities,
claims, damages and expenses incurred by an indemnified party and referred to
above in this Section 7 shall be deemed to include any legal or other expenses
reasonably incurred by such indemnified party in investigating, preparing or
defending against any litigation, or any investigation or proceeding by any
governmental agency or body, commenced or threatened, or any claim whatsoever
based upon any such untrue or alleged untrue statement or omission or alleged
omission.

     Notwithstanding the provisions of this Section 7, no International Manager
shall be required to contribute any amount in excess of the amount by which the
total price at which the International Securities underwritten by it and
distributed to the public were offered to the public exceeds the amount of any
damages which such International Manager has otherwise been required to pay by
reason of any such untrue or alleged untrue statement or omission or alleged
omission.

     No person guilty of fraudulent misrepresentation (within the meaning of
Section 11(f) of the 1933 Act) shall be entitled to contribution from any person
who was not guilty of such fraudulent misrepresentation.

     For purposes of this Section 7, each person, if any, who controls an
International Manager within the meaning of Section 15 of the 1933 Act or
Section 20 of the 1934 Act shall have the same rights to contribution as such
International Manager, and each director of the Company, each officer of the
Company who signed the Registration Statement, and each person, if any, who
controls the Company within the meaning of Section 15 of the 1933 Act or Section
20 of the 1934 Act shall have the same rights to contribution as the Company.
The International Managers' respective obligations to contribute pursuant to
this Section 7 are several in proportion to the number of Initial International
Securities set forth opposite their respective names in Schedule A hereto and
not joint.

                                       28
<PAGE>
 
     SECTION 8.  Representations, Warranties and Agreements to Survive Delivery.
                 --------------------------------------------------------------
All representations, warranties and agreements contained in this Agreement or in
certificates of officers of the Company, the Operating Partnership or any of the
Subsidiaries submitted pursuant hereto, shall remain operative and in full force
and effect, regardless of any investigation made by or on behalf of any
International Manager or controlling person, or by or on behalf of the Company,
and shall survive delivery of the Securities to the International Managers.

     SECTION 9.  Termination of Agreement.
                 ------------------------ 

     (a) Termination; General.  The Lead Managers may terminate this Agreement,
by notice to the Company, at any time at or prior to Closing Time (i) if there
has been, since the time of execution of this Agreement or since the respective
dates as of which information is given in the International Prospectus, any
material adverse change in the condition, financial or otherwise, or in the
earnings, business affairs or business prospects of the Company and its
subsidiaries considered as one enterprise, whether or not arising in the
ordinary course of business, or (ii) if there has occurred any material adverse
change in the financial markets in the United States or the international
financial markets, any outbreak of hostilities or escalation thereof or other
calamity or crisis or any change or development involving a prospective change
in national or international political, financial or economic conditions, in
each case the effect of which is such as to make it, in the judgment of the Lead
Managers, impracticable to market the Securities or to enforce contracts for the
sale of the Securities, or (iii) if trading in any securities of the Company has
been suspended or materially limited by the Commission or the New York Stock
Exchange, or if trading generally on the American Stock Exchange or the New York
Stock Exchange or in the Nasdaq National Market has been suspended or materially
limited, or minimum or maximum prices for trading have been fixed, or maximum
ranges for prices have been required, by any of said exchanges or by such system
or by order of the Commission, the NASD or any other governmental authority, or
(iv) if a banking moratorium has been declared by either Federal or New York
authorities.

     (b) Liabilities.  If this Agreement is terminated pursuant to this Section,
such termination shall be without liability of any party to any other party
except as provided in Section 4 hereof, and provided further that Sections 1, 6,
7 and 8 shall survive such termination and remain in full force and effect.

     SECTION 10.  Default by One or More of the International Managers.  If one
                  ----------------------------------------------------         
or more of the International Managers shall fail at Closing Time or a Date of
Delivery to purchase the Securities which it or they are obligated to purchase
under this Agreement (the "Defaulted Securities"), the Lead Managers shall have
the right, within 24 hours thereafter, to make arrangements for one or more of
the non-defaulting International Managers, or any other underwriters, to
purchase all, but not less than all, of the Defaulted Securities in such amounts
as may be agreed upon and upon the terms herein set forth; if, however, the Lead
Managers shall not have completed such arrangements within such 24-hour period,
then:

                                       29
<PAGE>
 
          (a)  if the number of Defaulted Securities does not exceed 10% of the
     number of International Securities to be purchased on such date, each of
     the non-defaulting International Managers shall be obligated, severally and
     not jointly, to purchase the full amount thereof in the proportions that
     their respective underwriting obligations hereunder bear to the
     underwriting obligations of all non-defaulting International Managers, or

          (b)  if the number of Defaulted Securities exceeds 10% of the number
     of International Securities to be purchased on such date, this Agreement
     or, with respect to any Date of Delivery which occurs after the Closing
     Time, the obligation of the International Managers to purchase and of the
     Company to sell the Option Securities to be purchased and sold on such Date
     of Delivery shall terminate without liability on the part of any non-
     defaulting International Manager.

     No action taken pursuant to this Section shall relieve any defaulting
International Manager from liability in respect of its default.

     In the event of any such default which does not result in a termination of
this Agreement or, in the case of a Date of Delivery which is after the Closing
Time, which does not result in a termination of the obligation of the
International Managers to purchase and the Company to sell the relevant
International Option Securities, as the case may be, either the Lead Managers or
the Company shall have the right to postpone Closing Time or the relevant Date
of Delivery, as the case may be, for a period not exceeding seven days in order
to effect any required changes in the Registration Statement or Prospectus or in
any other documents or arrangements.  As used herein, the term "International
Manager" includes any person substituted for an International Manager under this
Section 10.

     SECTION 11.  Notices.  All notices and other communications hereunder shall
                  -------                                                       
be in writing and shall be deemed to have been duly given if mailed or
transmitted by any standard form of telecommunication.  Notices to the
International Managers shall be directed to the Lead Managers c/o Merrill Lynch,
Pierce, Fenner & Smith Incorporated, North Tower, World Financial Center, New
York, New York 10281-1201, attention of Richard B. Saltzman; and notices to the
Company and the Operating Partnership shall be directed to it at 8 Arlington
Street, Boston, Massachusetts  02116, attention of Frederick J. DeAngelis, Esq.
Notices given by telex or telephone shall be confirmed in writing.

     SECTION 12.  Parties.  This Agreement shall each inure to the benefit of
                  -------                                                    
and be binding upon the International Managers and the Company and their
respective successors.  Nothing expressed or mentioned in this Agreement is
intended or shall be construed to give any person, firm or corporation, other
than the International Managers and the Company and their respective successors
and the controlling persons and officers and directors referred to in Sections 6
and 7 and their heirs and legal representatives, any legal or equitable right,
remedy or claim under or in respect of this Agreement or any provision herein
contained.  This Agreement and all conditions and provisions hereof are intended
to be for the sole and exclusive benefit of the International Managers and the
Company and their respective successors, and said controlling

                                       30
<PAGE>
 
persons and officers and directors and their heirs and legal representatives,
and for the benefit of no other person, firm or corporation.  No purchaser of
Securities from any International Manager shall be deemed to be a successor by
reason merely of such purchase.

     SECTION 13.  GOVERNING LAW AND TIME.  THIS AGREEMENT SHALL BE GOVERNED BY
                  ----------------------                                      
AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.  SPECIFIED
TIMES OF DAY REFER TO NEW YORK CITY TIME.

     SECTION 14.  Effect of Headings.  The Article and Section headings herein
                  ------------------                                          
and the Table of Contents are for convenience only and shall not affect the
construction hereof.

                                       31
<PAGE>
 
     If the foregoing is in accordance with your understanding of our agreement,
please sign and return to the Company a counterpart hereof, whereupon this
instrument, along with all counterparts, will become a binding agreement between
the International Managers and the Company in accordance with its terms.

                              Very truly yours,

                              BOSTON PROPERTIES, INC.


                              By
                                -------------------------------------
                                  Title:

                              BOSTON PROPERTIES LIMITED PARTNERSHIP


                              By
                                -------------------------------------
                                  Title:

CONFIRMED AND ACCEPTED,
 as of the date first above written:
MERRILL LYNCH INTERNATIONAL
GOLDMAN SACHS INTERNATIONAL
BEAR, STEARNS INTERNATIONAL LIMITED
MORGAN STANLEY & CO. INTERNATIONAL LIMITED
PAINEWEBBER INTERNATIONAL (UK) LTD.
PRUDENTIAL-BACHE SECURITIES (U.K.) INC.
SMITH BARNEY INC.

By: MERRILL LYNCH INTERNATIONAL


By 
   ----------------------------------------------
             Authorized Signatory


By: GOLDMAN SACHS INTERNATIONAL


- -------------------------------------------------

For themselves and as Lead Managers of the
other International Managers named in Schedule A hereto.

                                       32
<PAGE>
 
                                   SCHEDULE A



<TABLE> 
<CAPTION> 
                                                             Number of
                                                       Initial International
Name of International Manager                                Securities
- -----------------------------                                ----------
<S>                                                          <C> 
Merrill Lynch International ...........................
Goldman Sachs International ...........................
Bear, Stearns International Limited ...................
Morgan Stanley & Co. International Limited ............
PaineWebber International (UK) Ltd. ...................
Prudential-Bache Securities (U.K.) Inc. ...............
Smith Barney Inc. .....................................

                                                              ---------

Total .................................................       6,280,000
                                                              =========
</TABLE> 







                                   Sch A - 1
<PAGE>
 
                                   SCHEDULE B

                            BOSTON PROPERTIES, INC.

                        6,280,000 Shares of Common Stock
                           (Par Value $.01 Per Share)



          1.  The initial public offering price per share for the Securities,
determined as provided in said Section 2, shall be $_____.

          2.  The purchase price per share for the International Securities to
be paid by the several International Managers shall be $_____, being an amount
equal to the initial public offering price set forth above less $_____ per
share; provided that the purchase price per share for any International Option
Securities purchased upon the exercise of the over-allotment option described in
Section 2(b) shall be reduced by an amount per share equal to any dividends or
distributions declared by the Company and payable on the Initial International
Securities but not payable on the International Option Securities.




                                   Sch B - 1
<PAGE>
 
                                   SCHEDULE C

                               Certain Properties


599 Lexington Avenue
One Independence Square
Two Independence Square
Democracy Center
Capital Gallery
2300 N Street
Long Wharf Marriott
Cambridge Center Marriott







                                    Sch C-1
