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                                                                    Exhibit 10.1

                   REPRESENTATIONS, WARRANTIES AND AGREEMENTS
                                       OF
                     COHEN & STEERS CAPITAL MANAGEMENT, INC

The undersigned hereby certifies to Brandywine Realty Trust, a Maryland real
estate investment trust (the "Company"), that he is the duly appointed President
of Cohen & Steers Capital Management, Inc., a New York corporation ("C&S"), and
on behalf of C&S, pursuant to due authorization, does further hereby certify,
represent, warrant, and agree that:

1.       C&S acknowledges its understanding that the representations, warranties
         and agreements contained herein are made in order to obtain an
         exception for C&S to the ownership limitations (the "Ownership Limit")
         set forth in the Declaration of Trust, as amended to date (the
         "Articles"), of the Company. Such exception, which is sought with
         respect to the common shares of beneficial interest of the Company (the
         "Common Shares"), will allow C&S to be a "beneficial owner," as defined
         in Rule 13d-3 under the Securities Exchange Act of 1934, as amended (a
         "Rule 13d-3 Owner"), of up to, but not in excess of, 15.0% of the
         outstanding Common Shares (the "C&S Shares").

2.       C&S's ownership, as a Rule 13d-3 Owner, of the C&S Shares will not
         result in any Individual being the Tax Owner of Common Shares in excess
         of 9.8% of the value of all outstanding Common Shares. As used herein,
         the term "Tax Owner" of Common Shares shall mean the person who is
         considered to own such Common Shares applying the rules of Section
         856(h) of the Internal Revenue Code of 1986 (the "Code"), including the
         relevant provisions of Section 542(a)(2) and Section 544 as modified by
         Section 856(h) of the Code. The term "Individual" shall mean a natural
         person or an organization treated as an individual under the provisions
         of Section 542(a)(2) of the Code, applying the relevant rules of
         Section 856(h) of the Code.

3.       Neither C&S nor any Investor owns directly or indirectly any stock or
         other equity interest in excess of 9.8% in any Tenant. The term
         "Investor" means any owner of C&S or any open-end or closed-end fund
         for which C&S or an affiliate acts as an investment advisor. The term
         "Tenant" means any entity that leases space from the Company or from
         any direct or indirect subsidiary partnership, corporation or limited
         liability company in which Company owns an interest. C&S shall notify
         the Company in the event that C&S or any Investor acquires any stock or
         other equity interest in excess of 9.8% in any Tenant.

4.       C&S will not dispose of any of the C&S Shares in violation of the
         Ownership Limit or in a manner that would cause any Individual to be
         the Tax Owner of more than 9.8% of the outstanding Common Shares.

5.       C&S agrees that if, for any reason, (i) any of the above
         representations or warranties is violated, (ii) the ownership, as a
         Rule 13d-3 Owner, of the C&S Shares causes any Individual to be the Tax
         Owner of more than 9.8% of the outstanding Common Shares, (iii) C&S or
         any Investor acquires any stock or other equity interest in excess of
         9.8% in any Tenant, or (iv) in the sole reasonable judgment of the
         Company, the ownership, as a Rule 13d-3 Owner, of the C&S Shares could
         otherwise jeopardize the Company's tax status as a real estate
         investment trust for federal income tax purposes, then the waiver of
         the ownership limits granted by the Company to C&S shall be deemed void
         ab initio and shall result in a conversion of all or a portion (as
         reasonably determined by the Company to be necessary) of the C&S Shares
         into Excess Shares under the Articles.


<PAGE>

6.       C&S acknowledges its understanding that the foregoing exception to the
         Ownership Limit is only being granted to C&S, and not to any other
         person (including any of the Investors).

7.       C&S agrees that solely with respect to any Common Shares for which C&S
         is the beneficial owner as defined in Rule 13d-3 under the Securities
         Exchange Act of 1934, as amended, in excess of 9.8% of the outstanding
         Common Shares (such excess shares being referred to below as
         "Additional Shares"), C&S shall not take any actions that are
         inconsistent with its status as an investment manager that is eligible
         to file a Form 13G under the Securities Exchange Act of 1934 including
         the following:

         a.       Solicit proxies from shareholders of the Company, become a
                  "participant" in any "election contest" (as such terms are
                  used in Rule 14a-11 of the Securities Exchange Act of 1934, as
                  amended), with respect to the Company, or make any
                  communication (other than as required by law) referred to in
                  Rule 14a-1(l)(2)(iv) of the Securities Exchange Act of 1934,
                  as amended, in connection with any election contest or other
                  vote by shareholders of the Company or otherwise;

         b.       Vote for the removal of any member of the Board, except
                  removal "for cause" as such term is used under Maryland law,
                  except that this shall not limit C&S's ability to vote against
                  the reelection of a Board member;

         c.       Call or seek to have called any meeting of the shareholders of
                  the Company;

8.       Otherwise act, alone or in concert with others to (i) solicit, propose,
         seek to effect or negotiate with any other person with respect to (A)
         any business combination with the Company or (B) any restructuring,
         recapitalization or similar transaction of the Company, (ii) solicit,
         propose, seek to effect or negotiate with any other person with respect
         to, or announce an intent to make, any tender offer or exchange offer
         for any voting securities of the Company, or (iii) assist, participate
         in, facilitate or solicit any effort or attempt by any persons to do or
         seek to do any of the foregoing.

9.       The undersigned has the authority to execute this document on behalf
         of C&S.



<PAGE>


         IN WITNESS WHEREOF, I have executed this certificate as of this 27th
day of June, 2003.



Cohen & Steers Capital Management, Inc.



By: _____________________________
         Martin Cohen
         President





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                           WAIVER OF OWNERSHIP LIMITS

                      [BRANDYWINE REALTY TRUST LETTERHEAD]



                                                              June 27, 2003



Cohen & Steers Capital Management, Inc.
757 Third Avenue
New York, New York 10017

Re: Share Ownership Limits

         Reference is made to the Representations, Warranties and Agreements
executed as of July 1, 2003 of Cohen & Steers Capital Management, Inc. ("C&S")
to Brandywine Realty Trust (the "Company"), containing certain representations,
warranties and agreements, a copy of which is attached to this letter as
Attachment I (the "Representation Letter"). Based upon the Representation
Letter, the Company hereby advises you that an exception to the Ownership Limit
referred to in the Representation Letter has been established for C&S under the
Declaration of Trust of the Company effective as the date received on and
subject to the terms, conditions and limitations set forth in the Representation
Letter. Very truly yours,



BRANDYWINE REALTY TRUST





By:
     ------------------------------------------------
         Name: Gerard H. Sweeney
         Title: President and Chief Executive Officer



