1

                                                                     EXHIBIT 5.1

                                January 5, 2000

Scient Corporation
One Front Street, 28th Floor
San Francisco, California 94111

     Re:  Registration Statement on Form S-1
          ----------------------------------

Ladies and Gentlemen:

     We have examined the Registration Statement on Form S-1 (File No.
333-93441) originally filed by Scient Corporation (the "Company") with the
Securities and Exchange Commission (the "Commission") on December 22, 1999, as
thereafter amended or supplemented (the "Registration Statement"), in connection
with the registration under the Securities Act of 1933, as amended, of up to
2,702,500 shares of the Company's Common Stock (the "Shares"). The Shares, which
include an over-allotment option granted by the Company to the Underwriters to
purchase up to 352,500 additional shares of the Company's Common Stock, are to
be sold to the Underwriters by the Company and selling stockholders as described
in the Registration Statement for resale to the public. As your counsel in
connection with this transaction, we have examined the proceedings taken and are
familiar with the proceedings proposed to be taken by you in connection with the
sale and issuance of the Shares.

     It is our opinion that, upon completion of the proceedings being taken or
contemplated by us, as your counsel, to be taken prior to the issuance of the
Shares being sold by the Company and upon completion of the proceedings being
taken in order to permit such transactions to be carried out in accordance with
the securities laws of the various states where required, the Shares being sold
by the Company, when issued and sold in the manner described in the Registration
Statement and in accordance with the resolutions adopted by the Board of
Directors of the Company, will be legally and validly issued, fully paid and
non-assessable.

     We consent to the use of this opinion as an exhibit to said Registration
Statement and further consent to the use of our name wherever appearing in said
Registration Statement, including the prospectus constituting a part thereof,
and in any amendment or supplement thereto.

                                        Very truly yours,


                                        /s/ Gunderson Dettmer Stough
                                        Villeneuve Franklin & Hachigian, LLP