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                                                                     EXHIBIT 5.1

                                August 29, 2000


AFFILIATED Computer Services, Inc.
2828 North Haskell Avenue
Dallas, Texas  75204

         Re:      Registration Statement on Form S-8 of Affiliated Computer
                  Services, Inc.

Ladies and Gentlemen:

         We are acting as counsel for Affiliated Computer Services, Inc., a
Delaware corporation (the "Company"), in connection with the registration under
the Securities Act of 1933, as amended (the "Act"), of $5,000,000 of deferred
compensation obligations ("Deferred Compensation Obligations") to be registered
for the Company's 401(k) Supplemental Plan (the "Plan"). A Registration
Statement on Form S-8 covering the Deferred Compensation Obligations (the
"Registration Statement") is expected to be filed with the Securities and
Exchange Commission (the "Commission") on or about the date hereof.

         In reaching the conclusions expressed in this opinion, we have examined
and relied upon the originals or certified copies of all documents, certificates
and instruments as we have deemed necessary to the opinions expressed herein,
including the Company's Certificate of Incorporation, as amended, the Bylaws of
the Company and a copy of the Plan. In making the foregoing examinations, we
have assumed the genuineness of all signatures on original documents, the
authenticity of all documents submitted to us as originals and the conformity to
original documents of all copies submitted to us.

         Based solely upon the foregoing, and limited in all respects to the
laws of the State of Texas and the federal laws of the United States of America,
it is our opinion that the Deferred Compensation Obligations, when issued by the
Company in accordance with the terms of the Plan, will be valid and binding
obligations of the Company in accordance with and subject to the terms of the
Plan.

         We hereby consent to the use of this opinion as Exhibit 5 to the
Registration Statement.

                                       Very truly yours,

                                       /s/ HUGHES & LUCE, L.L.P.