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                                                                   Exhibit 10.27

                               February 1, 1999

To:  Russell DeLeon
Re:  Accelerated Vesting upon Acquisition

     In consideration of your services to Evolve Software, Inc. (the "Company"),
if there is any sale of all, or substantially all, of the assets of the Company,
or any merger or consolidation as a result of which the holders of the Company's
capital stock immediately prior to such transaction own less than 50% of the
capital stock of the combined company following such transaction (each, an
"Acquisition"), then any stock or options to purchase stock of the Company
("Subject Securities") held by, or authorized for issuance to, you prior to any
Acquisition shall have the following vesting terms, and the vesting or
repurchase option provisions of each stock option or restricted stock purchase
agreement between you and the Company is hereby and/or shall be amended to
effect the following vesting terms:

               (a) If you voluntarily terminate your employment or consulting
     prior to the one year anniversary of the Acquisition, there will be vesting
     only to such termination date without any acceleration or continued vesting
     of Subject Securities beyond the date of your voluntary termination; or

               (b) If your position is eliminated and/or you are not offered a
     position with comparable remuneration, responsibility, authority or
     location in the new or acquiring entity, there will be an acceleration of
     vesting of all Subject Securities; or

               (c) If your employment or consulting relationship is
     involuntarily terminated during the first year of such service in the new
     or acquiring entity, there will be an acceleration of vesting of Subject
     Securities until the second anniversary of the Acquisition; or

               (d) Upon your completion of one year of employment, consulting or
     other service in the new or acquiring entity, there will be an acceleration
     of vesting of Subject Securities to the second anniversary of the
     Acquisition.

     This agreement has been duly authorized by the Board of Directors of the
Company. Except for any accelerated vesting of Subject Securities, as set forth
above, this agreement does not create either an express and/or implied contract
of employment or compensation with the Company for any specified term. No waiver
or modification of this Agreement or of any covenant, condition, or limitation
herein contained shall be valid unless in writing and duly executed by you and
the Company. This Agreement shall be construed and enforced according to the
laws of the State of California. Please indicate your acceptance and agreement
to the terms set forth above by signing and dating this agreement below.

                                         Sincerely,

                                         /s/ John Bantleman
                                         -------------------------
                                         John Bantleman
                                         President and CEO



Accepted and agreed to:

By: /s/ J. Russell Deleon                Date: April 1, 1999
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