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                                                                     EXHIBIT 8.1

April 5, 2001

Sybase, Inc.
6475 Christie Avenue
Emeryville, CA 94608

Ladies and Gentlemen:

     We have acted as counsel to Sybase, Inc. ("Sybase"), a Delaware
corporation, in connection with (i) the exchange offer (the "Offer") made by
Neel Acquisition Corp. ("Merger Sub"), a Delaware corporation and wholly-owned
subsidiary of Sybase, to exchange shares of the common stock of Sybase for
shares of the common stock of New Era of Networks, Inc. (the "Company"), a
Delaware corporation, and (ii) the proposed merger (the "Merger") among Sybase,
Merger Sub and the Company, in each case pursuant to the Agreement and Plan of
Reorganization (the "Reorganization Agreement") dated as of February 20, 2001,
by and among Sybase, Merger Sub and the Company. The Merger, the Offer and
certain proposed transactions incident to the Merger and the Offer are described
in the Registration Statement on Form S-4 of Sybase (the "Registration
Statement"), which includes the preliminary prospectus of Sybase (the
"Preliminary Prospectus"). This opinion is being rendered pursuant to the
requirements of Item 21(a) of Form S-4 under the Securities Act of 1933, as
amended (the "Act"). Unless otherwise indicated, any capitalized terms used
herein and not otherwise defined have the meanings ascribed to them in the
Preliminary Prospectus.

     In connection with this opinion, we have examined and are familiar with the
Reorganization Agreement, the Registration Statement and such other presently
existing documents, records and matters of law as we have deemed necessary or
appropriate for purposes of our opinion. In addition, we have assumed (i) that
the Offer and the Merger will be consummated in the manner contemplated by the
Preliminary Prospectus and in accordance with the provisions of the
Reorganization Agreement, (ii) the truth and accuracy of the representations and
warranties made by Sybase and the Company in the Reorganization Agreement, (iii)
the truth and accuracy of the certificates of representations provided to us by
Sybase and Merger Sub and by the Company and (iv) such other documents as we
have deemed appropriate.

     Based upon and subject to the foregoing, in our opinion, the discussion
contained in the Registration Statement under the caption "The Offer -- Material
Federal Income Tax Consequences" accurately sets forth the material federal
income tax consequences generally applicable to the Offer and the Merger.
Because this opinion is being delivered prior to the Effective Time of the
Merger, it must be considered prospective and dependent on future events. There
can be no assurance that changes in the law will not take place that could
affect the United States federal income tax consequences of the Offer or the
Merger or that contrary positions may not be taken by the Internal Revenue
Service.

     No opinion is expressed as to any federal income tax consequences of the
Offer and the Merger except as specifically set forth herein, and this opinion
may not be relied upon except with respect to the consequences specifically
discussed herein.
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Sybase, Inc.
April 5, 2001
Page  2

     This opinion is furnished to you solely for use in connection with the
Registration Statement. We hereby consent to the filing of this opinion as an
exhibit to the Registration Statement. We also consent to the reference to our
firm name wherever appearing in the Registration Statement with respect to the
discussion of the material federal income tax consequences of the Offer and the
Merger, including the Preliminary Prospectus constituting a part thereof, and
any amendment thereto. In giving this consent, we do not thereby admit that we
are in the category of persons whose consent is required under Section 7 of the
Act or the rules and regulations of the Securities and Exchange Commission
thereunder, nor do we thereby admit that we are experts with respect to any part
of such Registration Statement within the meaning of the term "experts" as used
in the Act or the rules and regulations of the Securities and Exchange
Commission thereunder.

                                          Very truly yours,

                                          /s/ Wilson Sonsini Goodrich & Rosati
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                                          WILSON SONSINI GOODRICH & ROSATI
                                          PROFESSIONAL CORPORATION