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                                                                   EXHIBIT 10.73

                              FIFTH AMENDMENT TO
                   FIRST AMENDED AND RESTATED 1994 EMPLOYEE
                         STOCK AND UNIT OPTION PLAN OF
                   CHARLES E. SMITH RESIDENTIAL REALTY, INC.



     THIS FIFTH AMENDMENT TO FIRST AMENDED AND RESTATED 1994 EMPLOYEE STOCK AND
UNIT OPTION PLAN, dated as of January 23, 2001, is adopted by Charles E. Smith
Residential Realty, Inc., a Maryland corporation, for itself and as general
partner of Charles E. Smith Residential Realty L.P. (together, the "Company"),
and Smith Realty Company, Consolidated Engineering Services, Inc., and Smith
Management Construction, Inc. (collectively, the "Operating Subsidiaries").

     WHEREAS, the 1994 Employee Stock and Unit Option Plan (the "Plan") was
approved by the Board of Directors of Charles E. Smith Residential Realty, Inc.,
for itself and as a general partner of Charles E. Smith Residential Realty L.P.,
by unanimous written consents dated May 25, 1994, June 13, 1994, June 22, 1994,
and June 23, 1994, and at a meeting held on July 26, 1994, by the shareholders
of Charles E. Smith Residential Realty, Inc., by unanimous written consents
dated June 17, 1994, June 22, 1994, and June 23, 1994, and by the partners of
Charles E. Smith Residential Realty L.P. by unanimous written consents dated
June 17, 1994, and June 23, 1994, and the Plan, together with the 1994 Employee
Restricted Stock and Restricted Unit Plan and Directors Stock Option Plan, was
incorporated in a filing on Form S-8 with the Securities and Exchange Commission
(the "SEC"), which became effective on August 8, 1994;

     WHEREAS, the Board of Directors of the Company duly adopted and approved
(i) the First Amended and Restated 1994 Employee Stock and Unit Option Plan on
November 8, 1994, which was incorporated in a filing on Form 10-K for the year
ended December 31, 1994 and filed with the SEC on March 31, 1995, (ii) the First
Amendment thereto dated as of May 7, 1998, which was incorporated in a filing on
Form S-8 and filed with the SEC on November 17, 1998, (iii) the Second Amendment
thereto dated as of March 1, 1999; (iv) the Third Amendment thereto dated as of
October 25, 1999; and (v) the Fourth Amendment thereto dated as of January 25,
2000;

     WHEREAS, the Company and its stockholders did adopt the Plan for the
benefit of their employees and the employees of Smith Realty Company (formerly
Smith Property Management, Inc.), Consolidated Engineering Services, Inc., and
Smith Management Construction, Inc.;

     WHEREAS, the Board of Directors believes that it would be in the best
interests of the Company to increase the number of available option grants to
permit the continuation of this incentive program and to accommodate newly-hired
employees;

     WHEREAS, the Board of Directors of the Company, at its regular meeting on
January 23, 2001, approved a resolution increasing the number of shares or Units
available under the Plan as set forth below.

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     NOW, THEREFORE, in consideration of the premises herein set forth and other
good and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties hereto hereby amend the Plan, as follows:

     1.   Section 4 of the Plan is hereby amended and restated in its entirety
as follows:

          "The shares of Stock that may be issued pursuant to Incentive Awards
       may be (i) issued and outstanding shares of Stock or Units, (ii) treasury
       shares of Stock or Units (to the extent permitted by applicable law), or
       (iii) authorized but unissued shares. The number of shares of Stock and
       Units that may be issued pursuant to Incentive Awards under the Plan
       shall not exceed a combined 5,650,000 shares of Stock and Units. The
       Board of Directors of the Company shall determine how many shares of
       Stock and Units may be issued pursuant to the Incentive Awards to
       employees of Operating Subsidiaries. If any Incentive Award expires,
       terminates, or is terminated or canceled for any reason prior to exercise
       or vesting in full, the shares or Units that were subject to the
       unexercised, forfeited, or terminated portion of such Incentive Award
       shall be available immediately for future grants by the Granting Employer
       with respect thereto (subject to Section 12 hereof) of Incentive Awards
       under the Plan."

     2.   All capitalized terms used in this Fifth Amendment and not otherwise
defined shall have the meanings assigned to them in the Plan. Except as modified
herein, all terms and conditions of the Plan shall remain in full force and
effect, which terms and conditions the parties hereto ratify and affirm.

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     IN WITNESS WHEREOF, the undersigned have executed this FIFTH AMENDMENT TO
FIRST AMENDED AND RESTATED 1994 EMPLOYEE STOCK AND UNIT OPTION PLAN as of the
date first above written.


                         CHARLES E. SMITH RESIDENTIAL REALTY, INC.,
                         for itself and as general partner of Charles E. Smith
                         Residential Realty L.P.


                         BY: /s/ Ernest A. Gerardi, Jr.
                             --------------------------
                             Ernest A. Gerardi, Jr., President


This Fifth Amendment to the Plan was duly adopted and approved by the Board of
Directors of the Company at a meeting of the Board of Directors held on January
23, 2001.

                         /s/ Robert D. Zimet
                         -------------------
                         Robert D. Zimet
                         Secretary of the Company

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