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                                                                   EXHIBIT 10.19

                           AVALONBAY COMMUNITIES, INC.

                             SECRETARY'S CERTIFICATE

                                  AMENDMENTS TO
                         THE AVALONBAY COMMUNITIES, INC.
                            1994 STOCK INCENTIVE PLAN
                    AS AMENDED AND RESTATED ON APRIL 13, 1998

On May 6, 1999, at a duly called and held meeting of the Compensation Committee
of the Board of Directors of AvalonBay Communities, Inc. (the "Company") and at
a duly called and held meeting of the full Board of Directors of the Company,
such Committee and the Board adopted the following amendments to the AvalonBay
Communities, Inc. 1994 Stock Incentive Plan, as amended and restated on April
13, 1998 (the "Plan"):

            1.          The definition of "Retirement" set forth in Section 1 of
                        the Plan refers to the "retirement policy" of the
                        Company. To clarify its retirement policy for the
                        purposes of the Plan, the Company adopted the following
                        retirement policy for purposes of interpreting the
                        operation of the Plan after May 6, 1999:

                                 "Retirement" means (i) the employee's
                                 termination of employment with the Company and
                                 its Subsidiaries, other than for Cause, after
                                 attainment of age 55, but only if upon such
                                 termination of employment the employee has been
                                 employed in the aggregate for a period of at
                                 least 120 contiguous months by the Company, by
                                 any company of which the Company is the
                                 successor by name change or reincorporation, by
                                 Avalon Properties, Inc. or by Trammell Crow
                                 Residential, or any affiliate of any of the
                                 foregoing; and (ii) with respect to any
                                 employee of the Company who as of May 5, 1999
                                 has attained the age of 50 or more and who,
                                 upon retirement, has served in the capacity of
                                 senior vice president or a more senior position
                                 for at least one year (including service with
                                 Avalon Properties), "retirement" means the
                                 employee's termination of employment with the
                                 Company and its Subsidiaries other than for
                                 Cause."

            2.          A new Section 5(a)(vii)(C) to the Plan was adopted, such
                        section reading in its entirety as follows:

                                 "Any Stock Option held by an optionee whose
                                 employment by the Company and its Subsidiaries
                                 is terminated by reason of Retirement (but not
                                 if such termination qualifies as a retirement
                                 only under clause (ii) of the definition of
                                 Retirement) shall be automatically vested as of
                                 the date of termination of such employee's
                                 Retirement notwithstanding that the provisions
                                 of the related stock option agreement provide
                                 for forfeiture of the unvested portion of the
                                 award upon termination."

            3.          The following sentence was added at the end of Section
                        6(a) (Nature of Restricted Stock Awards), such sentence
                        reading in its entirety as follows:

                                 "In the event of termination of an employee by
                                 reason of Retirement (but not if such
                                 termination qualifies as a retirement only
                                 under clause (ii) of the definition of
                                 Retirement), then in such event any Restricted
                                 Stock Awards held by such employee on the date
                                 of termination shall continue to vest in
                                 accordance with

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                                 their terms following such termination,
                                 notwithstanding that the provisions of the
                                 Restricted Stock Award agreement provide for
                                 forfeiture of the unvested portion of the award
                                 upon termination."

            4.          The following sentence was added at the end of Section
                        7(a) (Nature of Deferred Stock Award), such sentence
                        reading in its entirety as follows:

                                 "In the event of termination of an employee by
                                 reason of Retirement (but not if such
                                 termination qualifies as a retirement only
                                 under clause (ii) of the definition of
                                 Retirement), then in such event any Deferred
                                 Stock Awards held by such employee on the date
                                 of termination shall continue to vest in
                                 accordance with their terms following such
                                 termination, notwithstanding that the
                                 provisions of the Deferred Stock Award
                                 agreement provide for forfeiture of the
                                 unvested portion of the award upon
                                 termination."

            IN WITNESS WHEREOF, the undersigned has signed this certificate as
of May 6, 1999.

                                        AVALONBAY COMMUNITIES, INC.

                                        /s/  Edward M. Schulman

                                        Name:       Edward M. Schulman
                                        Title:      Secretary