EXHIBIT 5.1

                   [Letterhead of Gibson, Dunn & Crutcher LLP]

                                                            July 10, 2000

(213) 229-7000

Computer Sciences Corporation
2100 East Grand Avenue
El Segundo, California 90245

         Re:      REGISTRATION STATEMENT OF FORM S-3

Ladies and Gentlemen:

We have acted as counsel to Computer Sciences Corporation (the "Corporation"), a
Nevada corporation, in connection with the registration under the Securities Act
of 1933, as amended (the "Securities Act"), pursuant to the Registration
Statement on Form S-3 (the "Registration Statement") to which this opinion is an
exhibit, of $300,000,000 of the Corporation's notes described in the
Registration Statement (the "Notes"). The Notes are being issued pursuant to an
indenture to be entered into by and between the Corporation and Citibank, N.A.
(the "Trustee") in substantially the form filed as an exhibit to the
Registration Statement (the "Indenture").

We have examined the originals or certified copies of such corporate records,
certificates of officers of the Corporation and/or public officials and such
other documents, and have made such other factual and legal investigations, as
we have deemed relevant and necessary as the basis for the opinions set forth
below. In such examination, we have assumed the genuineness of all signatures,
the legal capacity of natural persons, the authenticity of all documents
submitted to us as originals and the conformity to original documents of all
documents submitted to us as conformed or photostatic copies. In rendering this
opinion, we have further assumed the due and valid execution and delivery of the
Indenture by the Corporation and the Trustee in substantially the form filed as
an exhibit to the Registration Statement and that the Indenture constitutes the
legal, valid and binding agreement of the Trustee.

Based on the foregoing and in reliance thereon, and subject to the assumptions,
exceptions, qualifications and limitations contained herein and relying on the
statements of fact contained in the documents that we have examined, we are of
the opinion that (a) the Notes, upon the execution, authentication, delivery and
issuance thereof and timely payment in full therefor in the manner described in
the Indenture, the Registration Statement and the prospectus which forms a part
of the Registration Statement, will be validly issued, fully paid and
non-assessable and (b) the Notes so issued will be legally binding obligations
of the Corporation entitled to the benefits of the Indenture.

Our opinions set forth above are subject to the effect of (i) applicable
bankruptcy, reorganization, insolvency, moratorium and other similar laws and
court decisions of general application (including, without limitation, statutory
or other laws regarding fraudulent or preferential




transfers) relating to, limiting or affecting the enforcement of creditors'
rights generally, and (ii) general principles of equity, regardless of whether a
matter is considered in a proceeding in equity, at law or in arbitration,
including, without limitation, concepts of materiality, reasonableness, good
faith and fair dealing. Without limitation, we express no opinion as to the
ability to obtain specific performance, injunctive relief or other equitable
relief as a remedy for noncompliance with any of the Notes or the Indenture. We
further express no opinion as to the validity or legally binding nature of any
provisions in the Notes or the Indenture relating to indemnification,
exculpation or contribution or as to any provisions that may be construed as
imposing penalties or forfeitures.

Although we are not admitted to practice in the State of Nevada, we are
generally familiar with the General Corporation Law of the State of Nevada as
presently in effect and have made such inquiries as we consider necessary to
render the opinions related to Nevada law herein. Our opinions herein are
limited to matters involving the laws of the United States of America and the
State of New York and the General Corporation Law of the State of Nevada. We
express no opinion as to matters involving the laws of any other jurisdiction
(or any other laws of the State of Nevada). This opinion is limited to the
effect of the present state of the laws of the United States of America and the
State of New York and, to the limited extent set forth in the second preceding
sentence, the State of Nevada and the facts as they presently exist. In
rendering this opinion, we assume no obligation to revise or supplement this
opinion should the present laws, or the interpretation thereof, or such facts,
be changed.

We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to our name under the caption "Legal
Matters" in the prospectus which forms a part of the Registration Statement. In
giving this consent, we do not admit that we are within the category of persons
whose consent is required under Section 7 of the Securities Act or the General
Rules and Regulations of the Securities and Exchange Commission.

                                Very truly yours,

                               /s/ GIBSON, DUNN & CRUTCHER LLP
                               GIBSON, DUNN & CRUTCHER LLP



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