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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
___________, 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 "Notes"), constituting a series of Notes, described
in the Prospectus dated __________, 1998 (the "Prospectus") and issued pursuant
to an indenture dated as of ________, 1998, as supplemented and amended from
time to time (the "Indenture"), among the Operating Partnership, AMB Property
Corporation, certain of the Operating Partnership's subsidiaries and __________,
as trustee, in an aggregate principal amount of $___________. The Notes will be
issued and the terms thereof established in accordance with the Indenture, the
form of note attached hereto as Appendix A (the "Form of Note") and the
Prospectus, ________, 1998, included in the registration statement on Form S-11
filed with the Securities and Exchange Commission (the "Commission")
(Registration No. _________). The interest rate on the Notes will be___% upon
issuance and may be reset in accordance with Section 3 hereof and the Form of
Note. 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 Notes,
including, specifically, but without limitation, the calculation of any interest
rate for the Notes, 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 Notes.

        SECTION 3. Coupon Reset Process. If the Call Option is exercised in
accordance with the terms of the Form of Note 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 Notes 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, containing the names and addresses of
        three dealers, one of which shall be Morgan



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        Stanley & Co. Incorporated, from whom the Operating Partnership desires
        the Calculation Agent to obtain the Bids (as defined below) for the
        purchase of the Notes, 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 Notes, (b) a copy of the Form of Note
        and (c) a written request that each such Dealer submit a Bid to the
        Calculation Agent by 12:00 noon, 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 Notes settling on the Coupon
        Reset Date, and shall be quoted by such Dealer as a stated yield to
        maturity on the Notes ("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 Notes
        and (d) the method by which interest will be calculated on the Notes.

               (iii) The purchase price to be paid by any Dealer for the Notes
        (the "Purchase Price") shall be equal to (a) the total principal amount
        of the Notes, plus (b) a premium (the "Notes 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 ________, 2015 which has an interest rate of ____%,
        semi-annual interest payments on each _______ and _______, commencing
        _______, 2005, and a principal amount equal to the principal amount of
        the Notes, and assuming a discount rate equal to the Call Option
        Treasury Rate over (2) the principal amount of Notes. 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 at 11:00 am., 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 by 12:30 p.m., New York time (or within 30 minutes
        of such later time at which the last Bid is permitted to be received by
        the Calculation Agent, but in no event later than 3:30 p.m. New York
        time), 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 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



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        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 Notes Premium fully over the term
        of the Notes at the Yield to Maturity indicated by the Selected Bid. The
        Calculation Agent will notify the Dealer that submitted the Selected Bid
        by 4:00 p.m. New York time, 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 Notes will
        be effective from and including the Coupon Reset Date.

               (vi) The Callholder (as such term is defined in the Form of Note)
        shall sell such Notes to the Dealer that made the Selected Bid at the
        Purchase Price; such sale is to 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 Notes. The Calculation
Agent, in its individual capacity, and its officers, employees and shareholders,
may buy, sell, hold and deal in the Notes and may exercise any vote or join in
any action which any holder of the Notes 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.



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        SECTION 6. Duties of Calculation Agent. In acting under this Agreement
in connection with the Notes, 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 Notes.

        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 Notes,
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 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



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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.: ___________
                                              Telephone No.: (415) 394-9000
                                              Telecopy No.:  (415) 394-9001

              To the Trustee:

                                              Attn.: ___________
                                              Telephone No.:   (  ) _______
                                              Telecopy No.:    (  ) _______

              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 Notes 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.

        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.



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        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 ____________, 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 Note)



