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                                                                    EXHIBIT 10.6

                          CALCULATION AGENCY AGREEMENT
                                     BETWEEN
                        MORGAN STANLEY & CO. INCORPORATED
                                       AND
                               AMB PROPERTY, L.P.

        This Calculation Agency Agreement (the "Agreement"), dated as of June
__, 1998, is made between AMB Property, L.P. (the "Operating Partnership) and
Morgan Stanley & Co. Incorporated (the "Calculation Agent").

        The Operating Partnership proposes to issue and sell its Reset Put
Securities ("REPS(SM)") (the "Securities"), constituting a series of Securities,
described in the Prospectus dated June __, 1998 (the "Prospectus") and issued
pursuant to an indenture dated as of June __, 1998, as supplemented and amended
from time to time (the "Indenture"), among the Operating Partnership, AMB
Property Corporation and State Street Bank and Trust Company of California,
N.A., as trustee, in an aggregate principal amount of $___________. The
Securities will be issued and the terms thereof established in accordance with
the Indenture, the form of security attached hereto as Appendix A (the "Form of
Security") and the Prospectus included in the registration statement on Form
S-11 filed with the Securities and Exchange Commission (the "Commission")
(Registration No. 333-49163). The interest rate on the Securities will be___%
upon issuance and may be reset in accordance with Section 3 hereof and the Form
of Security. Capitalized terms used but not defined herein shall have the same
meanings as in the Indenture.

        SECTION 1. Appointment of Calculation Agent. The Operating Partnership
hereby appoints Morgan Stanley & Co. Incorporated as the Calculation Agent for
the purpose of calculating the Coupon Reset Rate (as defined below).

        SECTION 2. Status of Calculation Agent. Any acts taken by the
Calculation Agent under this Agreement or in connection with any Securities,
including, specifically, but without limitation, the calculation of any interest
rate for the Securities, shall be deemed to have been taken by the Calculation
Agent solely in its capacity as an agent acting on behalf of the Operating
Partnership and shall not create or imply any obligation to, or any agency or
trust relationship with, any of the owners or holders of the Securities.

        SECTION 3. Coupon Reset Process. If the Call Option is exercised in
accordance with the terms of the Form of Security and the Indenture, then the
following steps (the "Coupon Reset Process") shall be taken in order to
determine the interest rate to be paid on the Securities from and including the
Coupon Reset Date to the Stated Maturity Date (the "Coupon Reset Rate"). The
Operating Partnership and the Calculation Agent shall use reasonable efforts to
cause the actions contemplated below to be completed in as timely a manner as
possible.

               (i) The Operating Partnership shall provide the Calculation Agent
        with (a) a list (the "Dealer List"), no later than five Business Days
        prior to the Coupon Reset Date, 



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        containing the names and addresses of between three and five dealers,
        which shall include Morgan Stanley & Co. Incorporated, Goldman, Sachs &
        Co. and J.P. Morgan Securities, Inc., from whom the Operating
        Partnership desires the Calculation Agent to obtain the Bids (as defined
        below) for the purchase of the Securities, and (b) such other material
        as may reasonably be requested by the Calculation Agent to facilitate a
        successful Coupon Reset Process.

               (ii) Within one Business Day following receipt by the Calculation
        Agent of the Dealer List, the Calculation Agent shall provide to each
        dealer ("Dealer") on the Dealer List (a) a copy of the Prospectus
        relating to the offering of the Securities, (b) a copy of the Form of
        Security and (c) a written request that each such Dealer submit a Bid to
        the Calculation Agent not later than 3:00 p.m., New York time, on the
        third Business Day prior to the Coupon Reset Date (the "Bid Date"). The
        time on the Bid Date upon which Bids will be requested may be changed by
        the Calculation Agent, acting in its sole and absolute discretion to as
        late as 3:00 p.m. New York time. "Bid" shall mean an irrevocable written
        offer given by a Dealer for the purchase of all of the Securities
        settling on the Coupon Reset Date, and shall be quoted by such Dealer as
        a stated yield to maturity on the Securities ("Yield to Maturity"). Each
        Dealer shall also be provided with (a) the name of the Operating
        Partnership, (b) an estimate of the Purchase Price (which shall be
        stated as a US Dollar amount and be calculated by the Calculation Agent
        in accordance with clause (iii) below), (c) the principal amount and
        Stated Maturity Date of the Securities and (d) the method by which
        interest will be calculated on the Securities.

               (iii) The purchase price to be paid by any Dealer for the
        Securities (the "Purchase Price") shall be equal to (a) the total
        principal amount of the Securities, plus (b) a premium (the "Securities
        Premium") which shall be equal to the excess, if any, on the Coupon
        Reset Date of (1) the discounted present value to the Coupon Reset Date
        of a bond with a maturity of June ___, 2015 which has an interest rate
        of ____%, semi-annual interest payments on each June __ and December __,
        commencing December __, 2005, and a principal amount equal to the
        principal amount of the Securities, and assuming a discount rate equal
        to the Call Option Treasury Rate over (2) the principal amount of
        Securities. The "Call Option Treasury Rate" means the per annum rate
        equal to the offer side yield to maturity of the current on-the-run
        10-year United States Treasury Security per Telerate page 500, or any
        successor page not later than 3:00 p.m., New York time, on the Bid Date
        (or such other date and time that may be agreed upon by the Operating
        Partnership and the Calculation Agent) or, if such rate does not appear
        on Telerate page 500, or any successor page at such time, the rates on
        GovPX End-of-Day Pricing at 3:00 p.m., New York time, on the Bid Date
        (or such other date and time that may be agreed upon by the Operating
        Partnership and the Calculation Agent).

               (iv) The Calculation Agent shall provide written notice to the
        Operating Partnership as soon as practicable, on the Bid Date setting
        forth (a) the names of each of the Dealers from whom such Calculation
        Agent received Bids on the Bid Date, (b) the Bid submitted by each such
        Dealer and (c) the Purchase Price as determined pursuant to 



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        paragraph (iii) hereof. Except as provided below, the Calculation Agent
        shall thereafter select from the Bids received the Bid with the lowest
        Yield to Maturity (the "Selected Bid"); provided, however, that if such
        Calculation Agent has not received a timely Bid from a Dealer on or
        before the Bid Date, the Selected Bid shall be the lowest of all Bids
        received by such time; and provided further that if any two or more of
        the lowest Bids submitted are equivalent, the Operating Partnership
        shall in its sole discretion select any of such equivalent Bids (and
        such selected Bid shall be the Selected Bid). In all cases, Morgan
        Stanley & Co. Incorporated in its capacity as a Dealer has the right to
        match the Bid with the lowest Yield to Maturity, whereby Morgan Stanley
        & Co. Incorporated's Bid becomes the Selected Bid. The Calculation Agent
        shall set the Coupon Reset Rate equal to the interest rate which would
        amortize the Securities Premium fully over the term of the Securities at
        the Yield to Maturity indicated by the Selected Bid. The Calculation
        Agent will notify the Dealer that submitted the Selected Bid as soon as
        practicable, on the Bid Date that its Bid was determined to be the
        Selected Bid.

               (v) Immediately after calculating the Coupon Reset Rate, the
        Calculation Agent shall provide written notice to the Operating
        Partnership and the Trustee, setting forth such Coupon Reset Rate. At
        the request of the Holders, the Calculation Agent will provide to the
        Holders the Coupon Reset Rate. The Coupon Reset Rate for such Securities
        will be effective from and including the Coupon Reset Date.

               (vi) The Callholder (as such term is defined in the Form of
        Security) shall sell such Securities to the Dealer that made the
        Selected Bid at the Purchase Price; such sale shall be settled on the
        Coupon Reset Date in immediately available funds.

               (vii) In the event that the Call Option is terminated in
        accordance with its terms, the Coupon Reset Process shall also
        terminate.

        SECTION 4. Rights and Liabilities of the Calculation Agent. The
Calculation Agent shall incur no liability for, or in respect of, any action
taken, omitted to be taken or suffered by it in reliance upon any certificate,
affidavit, instruction, notice, request, direction, order, statement or other
paper, document or communication reasonably believed by it to be genuine. Any
order, certificate, affidavit, instruction, notice, request, direction,
statement or other communication from the Operating Partnership made or given by
it and sent, delivered or directed to the Calculation Agent under, pursuant to,
or as permitted by, any provision of this Agreement shall be sufficient for
purposes of this Agreement if such communication is in writing and signed by any
officer of the Operating Partnership's General Partner or attorney-in-fact of
the Operating Partnership. The Calculation Agent may consult with counsel
satisfactory to it and the advice of such counsel shall constitute full and
complete authorization and protection of such Calculation Agent with respect to
any action taken, omitted to be taken or suffered by it hereunder in good faith
and in accordance with and in reliance upon the advice of such counsel.

        SECTION 5. Right of Calculation Agent to Own Securities. The Calculation
Agent, in its individual capacity, and its officers, employees and shareholders,
may buy, sell, hold and deal in the Securities and may exercise any vote or join
in any action which any holder of the 



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Securities may be entitled to exercise or take as if it were not the Calculation
Agent. The Calculation Agent, in its individual capacity as such, may also
engage in or have an interest in any transaction with the Operating Partnership
or its affiliates as if it were not the Calculation Agent.

        SECTION 6. Duties of Calculation Agent. In acting under this Agreement
in connection with the Securities, the Calculation Agent shall be obligated only
to perform such duties as are specifically set forth herein and no other duties
or obligations on the part of such Calculation Agent, in its capacity as such,
shall be implied by this Agreement. In acting under this Agreement, the
Calculation Agent (in its capacity as such) assumes no obligation towards, or
any relationship of agency or trust for or with, the holders of the Securities.

        SECTION 7. Resignation of the Calculation Agent. The Calculation Agent
may resign at any time as Calculation Agent, such resignation to be effective
ten Business Days after the delivery to the Operating Partnership and the
Trustee of notice of such resignation. The Operating Partnership may appoint a
new Calculation Agent other than the incumbent Calculation Agent if the
incumbent Calculation Agent resigns. If a new Calculation Agent is appointed
pursuant to this Section 7, the Operating Partnership shall provide the Trustee
with notice thereof.

        SECTION 8. Appointment of Successor Calculation Agent. Any successor
Calculation Agent appointed by the Operating Partnership shall execute and
deliver to the incumbent Calculation Agent and to the Operating Partnership an
instrument accepting such appointment and thereupon such successor Calculation
Agent shall, without any further act or instrument, become vested with all the
rights, immunities, duties and obligations of the incumbent Calculation Agent,
with like effect as if originally named as initial Calculation Agent hereunder,
and the incumbent Calculation Agent shall thereupon be obligated to transfer and
deliver, and such successor Calculation Agent shall be entitled to receive and
accept, copies of any available records maintained by the incumbent Calculation
Agent in connection with the performance of its obligations hereunder.

        SECTION 9. Indemnification. The Operating Partnership shall indemnify
and hold harmless Morgan Stanley & Co. Incorporated, or any successor
Calculation Agent thereof, and their respective officers and employees from and
against all actions, claims, damages, liabilities and losses, and costs and
expenses related thereto (including but not limited to reasonable legal fees and
costs) relating to or arising out of actions or omissions in any capacity
hereunder, except actions, claims, damages, liabilities, losses, costs and
expenses caused by the bad faith, gross negligence or willful misconduct of
Morgan Stanley & Co. Incorporated or any successor Calculation Agent, or their
respective Officers or employees. This Section 9 shall survive the termination
of the Agreement and the payment in full of all obligations under the
Securities, whether by redemption, repayment or otherwise.

        SECTION 10. Merger, Consolidation or Sale of Business by Calculation
Agent. Any corporation or other entity into which the Calculation Agent may be
merged, converted or consolidated, or any corporation or other entity resulting
from any merger, conversion or 


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consolidation to which such Calculation Agent may be a party, or any corporation
or other entity to which such Calculation Agent may sell or otherwise transfer
all or substantially all of its business, shall, to the extent permitted by
applicable law, become the Calculation Agent under this Agreement without the
execution of any document or any further act by the parties hereto.

        SECTION 11. Notices. Any notice or other communication required to be
given hereunder shall be delivered in person, sent by letter, telecopy or
facsimile or communicated by telephone (subject, in the case of communication by
telephone, to written confirmation dispatched within twenty-four (24) hours) to
the addresses given below or such other address as each party hereto may
subsequently designate in writing,

     To the Operating Partnership:      AMB Property, L.P.
                                        505 Montgomery Street
                                        San Francisco, CA 94111
                                        Attn.: Chief Financial Officer
                                        Telephone No.: (415) 394-9000
                                        Telecopy No.:  (415) 394-9001

                                        With a copy to:

                                        AMB Property, L.P.
                                        505 Montgomery Street
                                        San Francisco, CA 94111
                                        Attn.: General Counsel
                                        Telephone No.: (415) 394-9000
                                        Telecopy No.:  (415) 394-9001

     To the Trustee:                    State Street Bank and Trust Company of
                                        California, N.A.
                                        633 West Fifth Street, 12th Floor
                                        Los Angeles, CA 90071
                                        Attn.: Corporate Trust Department
                                        Telephone No.: (213) 362-7345
                                        Telecopy No.:  (213) 362-7357

     To the Calculation Agent:          Morgan Stanley & Co. Incorporated
                                        1585 Broadway, 3rd Floor
                                        New York, New York 10036
                                        Attention:
                                        Telephone No.: (212) 76l-2566
                                        Telecopy No.:  (212) 76l-0580

Any notice hereunder given by telecopy shall be deemed to have been given when
transmitted. Any notice hereunder given by letter shall be deemed to have been
given five Business Days after mailing such notice.

        SECTION 12. Benefit of Agreement. Except as provided herein, this
Agreement is solely for the benefit of the parties hereto and their successors
and assigns, and no other person shall acquire or have any rights under or by
virtue hereof. The terms "successors" and "assigns" shall not include any
purchasers of any Securities merely because of such purchase.

        SECTION 13. Governing Law. This Agreement shall be governed by and
construed in accordance with the laws of the State of New York applicable to
agreements entered into and performed in such State.



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        SECTION 14. Severability. If any provision of this Agreement shall be
held or deemed to be or shall, in fact, be invalid, inoperative or unenforceable
as applied in any particular case in any or all jurisdictions because it
conflicts with any provision of any constitution, statute, rule or public policy
or for any other reason, such circumstances shall not have the effect of
rendering the provision in question invalid, inoperative or unenforceable in any
other case, circumstances or jurisdictions or of rendering any other provision
or provisions of this Agreement invalid, inoperative or unenforceable to any
extent whatsoever.

        SECTION 15. Counterparts. This Agreement may be executed in several
counterparts, each of which shall be regarded as an original and all of which
shall constitute one and the same instrument.

        SECTION 16. Amendments. This Agreement may be amended by any instrument
in writing executed and delivered by each of the parties hereto.

        IN WITNESS WHEREOF, this Agreement has been entered into as of the
___________ day of June, 1998.

                                     AMB PROPERTY, L.P.

                                     By:  AMB PROPERTY CORPORATION,
                                     as General Partner



                                     By: _______________________________________
                                          Name:
                                          Title:

                                     MORGAN STANLEY & CO. INCORPORATED



                                     By: _______________________________________
                                          Name:
                                          Title:



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                                   Appendix A

                               (Form of Security)


