EXHIBIT 5.1

                                 March 16, 2000

CrossWorlds Software
577 Airport Boulevard, Suite 800
Burlingame, CA 94010


         Registration Statement on Form S-1 (File No. 333-96055)

Ladies and Gentlemen:

         We have examined the amended Registration Statement on Form S-1 (File
No. 333-96055) (the "Registration Statement") filed by you with the Securities
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and Exchange Commission on February 3, 2000, in connection with the registration
under the Securities Act of 1933 of shares of your Common Stock (the "Shares").
As your legal counsel in connection with this transaction, we have examined the
proceedings taken and we 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
in order to permit such transactions to be carried out in accordance with the
securities laws of the various states where required, the Shares, when issued
and sold in the manner described in the Registration Statement, will be legally
and validly issued, fully paid and nonassessable.

         We consent to the use of this opinion as an exhibit to the Registration
Statement and further consent to the use of our name wherever it appears in the
Registration Statement and in any amendment to it.

                                                      Sincerely,

                                                      VENTURE LAW GROUP
                                                      A Professional Corporation
                                                      /s/ Venture Law Group