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                                                                   EXHIBIT 10.21

                               THE IRVINE COMPANY
                            550 Newport Center Drive
                             Newport Beach, CA 92660


                                February 1, 1999


Irvine Apartment Communities, Inc.
550 Newport Center Drive
Newport Beach, CA 92660


Gentlemen:

               In connection with that certain Agreement and Plan of Merger,
dated as of February 1, 1999 (the "Merger Agreement"), between TIC Acquisition
LLC ("Acquiror") and Irvine Apartment Communities, Inc. (the "Company"), you
have requested that The Irvine Company ("TIC") make certain representations,
warranties and covenants. In order to facilitate the transactions contemplated
by the Merger Agreement, TIC hereby makes the representations, warranties and
covenants set forth in this letter agreement. All capitalized terms not defined
herein shall have the meanings set forth in the Merger Agreement.

               1. Ownership of Acquiror/Availability of Funds. All of Acquiror's
membership interests are owned by TIC and a wholly-owned Subsidiary of TIC. TIC
is the sole managing member of Acquiror. TIC shall take no action that would
cause Acquiror not to have a minimum of $150 million of cash on hand from the
date of the Merger Agreement through the earlier of (i) the Effective Time and
(ii) sixty (60) days following the termination of the Merger Agreement pursuant
to the terms thereof. Prior to the earlier of (i) the Effective Time and (ii)
sixty (60) days following the termination of the Merger Agreement pursuant to
the terms thereof, TIC shall not permit Acquiror to engage in any business or
transaction other than business or transactions related to the transactions
contemplated by the Merger Agreement.

               2. Ownership of Stock. From the date hereof to the earlier of (i)
the Effective Time and (ii) the termination of the Merger Agreement pursuant to
the terms thereof, TIC shall not, and shall not permit any of its Subsidiaries
to, sell or otherwise dispose of any of the shares of Company Common Stock owned
by them. At the Company Stockholders Meeting, or any adjournment thereof, TIC
shall, and shall cause its Subsidiaries to, vote the shares of Company Common
Stock owned by them in favor of the Merger.

               3. Cooperation. TIC shall take all actions necessary to cooperate
with Acquiror, and shall take all actions necessary to cause Acquiror to comply
with its obligations, in connection with Sections 5.1(a), 5.8 and 5.9 (insofar
as it pertains to insurance only) of the Merger Agreement; provided that with
respect to Section 5.9 of the Merger Agreement, TIC shall be deemed to have
satisfied its obligations hereunder (and the obligations of Acquiror under the




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Merger Agreement) by causing Acquiror to purchase an appropriate policy of
insurance. TIC agrees to cooperate with Acquiror and the Company in connection
with the Merger Agreement and to use reasonable efforts to cause Acquiror to
consummate the Merger; provided that TIC shall have no obligation to contribute
any funds to Acquiror in connection with the Merger.

               The rights and obligations of the parties to this letter
agreement shall bind and inure to the benefit of the respective successors and
assigns of the parties hereto.

               This letter agreement shall be governed by and construed in
accordance with the laws of the State of Delaware, without giving effect to
conflicts of law principles.

               This letter agreement constitutes the full and complete
understanding and agreement of the parties hereto and supersedes all prior
understandings and agreements with respect to the subject matter hereof. Any
waiver, modification or amendment of any provision of this letter agreement
shall be effective only if in writing and signed by the parties hereto.





                            [Signature Page Follows]




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               If the foregoing reflects your understanding of our agreement
concerning the matters set forth herein, please sign a copy of this letter
agreement where indicated below and return it to me.



                                            Very truly yours,

                                            The Irvine Company

                                            By:  /s/ MICHAEL D. MCKEE
                                                 -------------------------------
                                                 Michael D. McKee
                                                 Chief Financial Officer





The terms and conditions of the preceding letter agreement are accepted and
agreed to by the following:


                                            Irvine Apartment Communities, Inc.



                                            By:  /s/ WILLIAM H. MCFARLAND
                                                 -------------------------------
                                                 William H. McFarland
                                                 Chief Executive Officer









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