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                                                                    Exhibit 10.4

                                PARENT AGREEMENT
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         THIS PARENT AGREEMENT ("Agreement") dated as of November 1, 2001 is
executed and delivered by ARCHSTONE-SMITH TRUST, a Maryland real estate
investment trust ("Parent"), in favor of (a) THE CHASE MANHATTAN BANK, in its
capacity as Agent (the "Agent") for the Lenders under that certain Credit
Agreement dated as of December 20, 2000 by and among ARCHSTONE COMMUNITIES
TRUST, now known as ARCHSTONE-SMITH OPERATING TRUST (the "Borrower"), the
financial institutions party thereto and their assignees in accordance therewith
(the "Lenders"), and the Agent (as the same has been amended by an amendment
dated September 21, 2001 and an amendment dated of even date herewith, and as
the same may be further amended, restated, supplemented or otherwise modified
from time to time in accordance with its terms, the "Credit Agreement") and (b)
the Lenders.

         WHEREAS, pursuant to the Credit Agreement, the Lenders have made
available to the Borrower certain financial accommodations on the terms and
conditions set forth in the Credit Agreement;

         WHEREAS, the Borrower is a Subsidiary of the Parent; and

         WHEREAS, the Borrower and the Parent have determined it to be in their
mutual best interests to obtain financing for the Borrower from the Agent and
the Lenders through their collective efforts.

         NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged by the Parent, the Parent agrees as
follows:

         Section 1. Receipt, Certificate. The Parent acknowledges that it has
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received a copy of the Credit Agreement. The capitalized terms used in this
Agreement and not otherwise defined herein shall have the respective meanings
ascribed to them in the Credit Agreement. The Parent agrees to provide the
Officer's Certificate referenced in Section 6 of the Agreement and First
Amendment to Credit Agreement dated as of September 21, 2001.

         Section 2. Legal Requirements. The Parent will comply with all Legal
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Requirements to maintain, and will at all times elect, qualify as and maintain,
its status as a real estate investment trust under Section 856(c)(1) of the
Code.

         Section 3. Legal Compliance. The Parent will (a) maintain at least one
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class of common shares of the Parent having trading privileges on the New York
Stock Exchange or the American Stock Exchange, or which is listed on The NASDAQ
Stock Market's National Market; (b) own, directly or indirectly, at least
fifty-one percent (51%) of (i) the shares of beneficial interest of the
Borrower, and (ii) the Class A-2 Common Units of the Borrower and any other
class of security

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issued by the Borrower with the power to elect the Trustees of the Borrower; (c)
maintain management and control of the Borrower; and (d) not sell, transfer or
convey any of the shares of beneficial interest of the Borrower owned by the
Parent, except (i) in payment of the purchase price of Property (including
mergers with and acquisitions of Persons) acquired by the Borrower. (ii) upon
conversion or redemption of securities of the Borrower in accordance with their
terms or (iii) upon any repurchase by the Borrower of the Borrower's securities
from the Parent in connection with a repurchase by the Parent of the Parent's
securities.

         Section 4. Negative Covenants. The Parent will not (a) have any
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Subsidiary that is a "qualified REIT subsidiary" under Section 856 of the Code
other than the QRS Entities; (b) own any Property other than the ownership
interests of the Borrower, and the Parent's ownership interests as of the date
of the Merger in the QRS Entities; (c) give or allow any Lien on any of its
Property including the ownership interests of the Borrower; and (d) create,
incur, suffer or permit to exist, or assume or guarantee, directly or
indirectly, contingently or otherwise, or become or remain liable with respect
to (i) any Indebtedness if the aggregate of such Indebtedness and the
Indebtedness of the Borrower would violate Sections 5.3(a), (b), (c) or (e) if
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such aggregate Indebtedness is treated as the Borrower's Indebtedness, and (ii)
any Indebtedness of a Person other than the Parent.

         Section 5. Conduct of Business. The Parent will hold all of its assets
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and conduct all of its operations through the Borrower, the QRS Entities that
are in existence on the date hereof and one or more of the Borrower's
Subsidiaries.

         Section 6.  Governing Law.  THIS AGREEMENT SHALL BE GOVERNED BY, AND
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CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF TEXAS.

         Section 7.  JURISDICTION, VENUE.
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         (a) THE FEDERAL DISTRICT COURT OF THE SOUTHERN DISTRICT OF TEXAS,
HOUSTON DIVISION, OR, AT THE OPTION OF THE AGENT, ANY STATE COURT LOCATED IN
HARRIS COUNTY, TEXAS SHALL HAVE NON-EXCLUSIVE JURISDICTION TO HEAR AND DETERMINE
ANY CLAIMS OR DISPUTES BETWEEN OR AMONG THE PARENT, THE AGENT OR ANY OF THE
LENDERS, PERTAINING DIRECTLY OR INDIRECTLY TO THIS AGREEMENT OR ANY OTHER CREDIT
DOCUMENT OR TO ANY MATTER ARISING HEREFROM OR THEREFROM. THE PARENT EXPRESSLY
SUBMITS AND CONSENTS IN ADVANCE TO SUCH JURISDICTION IN ANY ACTION OR PROCEEDING
COMMENCED IN SUCH COURTS. THE CHOICE OF FORUM SET FORTH IN THIS SECTION SHALL
NOT BE DEEMED TO PRECLUDE THE BRINGING OF ANY ACTION BY THE AGENT OR ANY LENDER
OR THE ENFORCEMENT BY THE AGENT OR ANY LENDER IN ANY OTHER APPROPRIATE
JURISDICTION. FURTHER, THE PARENT IRREVOCABLY WAIVES, TO THE FULLEST EXTENT
PERMITTED BY APPLICABLE LAW, ANY OBJECTION WHICH

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IT MAY NOW OR HEREAFTER HAVE TO THE LAYING OF THE VENUE OF ANY SUCH PROCEEDING
BROUGHT IN SUCH A COURT AND ANY CLAIM THAT ANY SUCH PROCEEDING BROUGHT IN SUCH A
COURT HAS BEEN BROUGHT IN AN INCONVENIENT FORUM.

         (b) THE FOREGOING WAIVERS HAVE BEEN MADE WITH THE ADVICE OF COUNSEL AND
WITH A FULL UNDERSTANDING OF THE LEGAL CONSEQUENCES THEREOF, AND SHALL SURVIVE
THE PAYMENT OF THE OBLIGATIONS AND THE TERMINATION OF THIS AGREEMENT.

         Section 8.   Waiver of Remedies. No delay or failure on the part of the
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Agent or the Lenders in the exercise of any right or remedy it may have against
the Parent hereunder or otherwise shall operate as a waiver thereof, and no
single or partial exercise by the Agent or the Lenders of any such right or
remedy shall preclude other or further exercise thereof or the exercise of any
other such right or remedy.

         Section 9.   Successors and Assigns. Each reference herein to the Agent
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or the Lenders shall be deemed to include such Person's respective successors
and assigns (including, but not limited to, any holder of the Obligations) in
whose favor the provisions of this Agreement also shall inure, and each
reference herein to the Parent shall be deemed to include the Parent's
successors and assigns, upon whom this Agreement also shall be binding. The
Lenders and the Agent may, in accordance with the applicable provisions of the
Credit Agreement, assign, transfer or sell any Obligation, or grant or sell
participation in any Obligations, to any Person or entity without the consent
of, or notice to, the Parent and without releasing, discharging or modifying the
Parent's obligations hereunder. The Parent may not assign or transfer its
obligations hereunder to any Person.

         Section 10.  Amendments.  This Agreement may not be amended except as
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provided in the Credit Agreement.

         Section 11.  Notices.   All notices, requests and other communications
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hereunder shall be in writing and shall be given as provided in the Credit
Agreement.  The Parent's address for notice is set forth below its signature
hereto.

         Section 12. Severability. In case any provision of this Agreement shall
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be invalid, illegal or unenforceable in any jurisdiction, the validity, legality
and enforceability of the remaining provisions shall not in any way be affected
or impaired thereby.

         Section 13.  Headings.  Section headings used in this Agreement are for
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convenience only and shall not affect the construction of this Agreement.

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         IN WITNESS WHEREOF, the Parent has duly executed and delivered this
Agreement as of the date and year first written above.

                                   ARCHSTONE-SMITH TRUST



                                   By: /s/ Jack R. Callison, Jr.
                                      ------------------------------------------
                                   Name:  Jack R. Callison, Jr.
                                        ----------------------------------------
                                   Title:  Vice President
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                                   Address for Notices:

                                   Archstone-Smith Trust
                                   7670 S. Chester Street, Suite 100
                                   Englewood, Colorado 80112
                                   Attention:  Charles E. Mueller, Jr.

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