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                                                                    EXHIBIT 4.12


         TRUST AGREEMENT, dated as of July 25, 2001 among Affiliated Computer
Services, Inc., a Delaware corporation, as Sponsor (the "Sponsor"), and
Wilmington Trust Company, as trustee (the "Property Trustee" and the "Delaware
Trustee"), and William L. Deckelman, Jr. and Warren Edwards, each as a trustee
(the "Regular Trustees") (the Property Trustee, the Delaware Trustee and the
Regular Trustees, collectively the "Trustees"). The Sponsor and the Trustees
hereby agree as follows:

         1. The Delaware business trust created hereby shall be known as "ACS
Trust II" (the "Trust"), in which name the Trustees, or the Sponsor to the
extent provided herein, may conduct the business of the Trust, make and execute
contracts, and sue and be sued.

         2. The Sponsor hereby assigns, transfers, conveys and sets over to the
Trust the sum of $10. The Trust hereby acknowledges receipt of such amount from
the Sponsor, which amount shall constitute the initial trust estate. It is the
intention of the parties hereto that the Trust created hereby constitute a
business trust under Chapter 38 of Title 12 of the Delaware Code, 12 Del. Code
Section 3801 et seq. (the "Business Trust Act"), and that this document
constitute the governing instrument of the Trust. The Trustees are hereby
authorized and directed to execute and file a certificate of trust with the
Secretary of State of the State of Delaware in the form attached hereto in
accordance with the provisions of the Business Trust Act. The Trust is hereby
established by the Sponsor and the Trustees for the purposes of (i) issuing
preferred securities representing undivided beneficial interests in the assets
of the Trust ("Preferred Securities") in exchange for cash and investing the
proceeds thereof in junior subordinated debt securities of the Sponsor, (ii)
issuing and selling common securities representing an undivided beneficial
interest in the assets of the Trust ("Common Securities") to the Sponsor in
exchange for cash and investing the proceeds thereof in additional junior
subordinated debt securities of the Sponsor and (iii) engaging in such other
activities as are necessary, convenient or incidental thereto.

         3. The Sponsor and the Trustees will enter into an Amended and Restated
Trust Agreement, satisfactory to each such party and substantially in the form
included as an exhibit to the Securities Act Registration Statement referred to
below, to provide for the contemplated operation of the Trust created hereby and
the issuance of the Preferred Securities and Common Securities referred to
therein. Prior to the execution and delivery of such Amended and Restated Trust
Agreement, the Trustees shall not have any duty or obligation hereunder or with
respect to the trust estate, except as otherwise required by applicable law or
as may be necessary to obtain prior to such execution and delivery any licenses,
consents or approvals required by applicable law or otherwise.

         4. The Sponsor, as the sponsor of the Trust, is hereby authorized (i)
to prepare and file with the Securities and Exchange Commission (the
"Commission") and execute, in each case on behalf of the Trust, (a) a
Registration Statement on Form S-3 or on such other form or forms as may be
appropriate, including without limitation any registration statement of the type
contemplated by Rule 462(b) of the Securities Act of 1933, as amended (the
"Securities Act") (any such registration statement, whether on Form S-3, another
form or under Rule 462(b) being referred to herein as the "Securities Act

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Registration Statement"), including any pre-effective or post-effective
amendments to such Registration Statement, relating to the registration under
the Securities Act of the Preferred Securities and certain other securities of
the Sponsor and (b) if the Sponsor shall deem it desirable, a Registration
Statement on Form 8-A (the "Exchange Act Registration Statement"), including all
pre-effective and post-effective amendments thereto, relating to the
registration of the Preferred Securities under Section 12 of the Securities
Exchange Act of 1934, as amended; (ii) if the Sponsor shall deem it desirable,
to prepare and file with New York Stock Exchange, Inc. or any other automated
quotation system, exchange or over-the-counter market (collectively, the
"Exchanges") and execute on behalf of the Trust a listing application or
applications and all other applications, statements, certificates, agreements
and other instruments as shall be necessary or desirable to cause the Preferred
Securities to be listed on any Exchange; (iii) to prepare and file and execute
on behalf of the Trust such applications, reports, surety bonds, irrevocable
consents, appointments of attorney for service of process and other papers and
documents as the Sponsor, on behalf of the Trust, may deem necessary or
desirable to register the Preferred Securities under the securities or "Blue
Sky" laws of such jurisdictions as the Sponsor, on behalf of the Trust, may deem
necessary or desirable; (iv) to negotiate the terms of and execute on behalf of
the Trust an underwriting or other purchase agreement among the Trust, the
Sponsor and any underwriter(s), dealer(s) or agent(s) relating to the Preferred
Securities, as the Sponsor, on behalf of the Trust, may deem necessary or
desirable; and (v) to execute and deliver on behalf of the Trust letters or
documents to, or instruments for filing with, a depository relating to the
Preferred Securities. In the event that any filing referred to in clauses
(i)-(iii) above is required by the rules and regulations of the Commission, any
Exchange, the National Association of Securities Dealers, Inc. or state
securities or blue sky laws, to be executed on behalf of the Trust by a Trustee,
any natural person appointed pursuant to Section 6 hereof, in his or her
capacity as trustee of the Trust, and the Sponsor are hereby authorized to join
in any such filing and to execute on behalf of the Trust any and all of the
foregoing.

         5. This Trust Agreement may be executed in one or more counterparts.

         6. The number of Trustees initially shall be three (3) and thereafter
the number of Trustees shall be such number as shall be fixed from time to time
by a written instrument signed by the Sponsor that may increase or decrease the
number of Trustees; provided, however, that the number of Trustees shall in no
event be less than three (3); and provided, further that to the extent required
by the Business Trust Act, one Trustee shall either be a natural person who is a
resident of the State of Delaware or, if not a natural person, an entity that
has its principal place of business in the State of Delaware and meets other
requirements imposed by applicable law. Subject to the foregoing, the Sponsor is
entitled to appoint or remove without cause any Trustee at any time. Any Trustee
may resign upon thirty days' prior notice to the Sponsor.

         7. The Trust may be dissolved and terminated at the election of the
Sponsor.

         8. The Delaware Trustee, in its capacity as trustee, shall not have the
powers or duties of the Trustee set forth herein (except as may be required
under the Business Trust Act) and shall be a Trustee hereunder for the sole and
limited purpose of fulfilling the requirements of Section 3807(a) of the
Business Trust Act.

         9. This Declaration of Trust shall be governed by, and construed in
accordance with, the laws of the State of Delaware (without regard to conflict
of laws principles).


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         IN WITNESS WHEREOF, the parties hereto have caused this Declaration of
Trust to be duly executed as of the day and year first above written.


                                       AFFILIATED COMPUTER SERVICES, INC.,
                                       as Sponsor


                                       By: /s/ MARK KING
                                           -------------------------------------
                                           Name: Mark King
                                           Title: Chief Operating Officer


                                       WILMINGTON TRUST COMPANY,
                                       as Property Trustee


                                       By: /s/ JAMES P. LAWLER
                                           -------------------------------------
                                           Name: James P. Lawler
                                           Title: Vice President


                                       WILMINGTON TRUST COMPANY,
                                       as Delaware Trustee


                                       By: /s/ JAMES P. LAWLER
                                           -------------------------------------
                                           Name: James P. Lawler
                                           Title: Vice President


                                       WILLIAM L. DECKELMAN, JR.,
                                       as Regular Trustee


                                       /s/ WILLIAM L. DECKELMAN
                                       -----------------------------------------


                                       WARREN EDWARDS,
                                       as Regular Trustee


                                       /s/ WARREN EDWARDS
                                       -----------------------------------------