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                                                        EXHIBIT 10.25


[PRISM LOGO]

PRISM SOLUTIONS, INC.
1000 HAMLIN COURT
SUNNYVALE, CA 94089

January 20, 1997

Warren M. Weiss
90 Skywood Way
Woodside, CA 94062

        Re:  Employment With Prism Solutions, Inc.

Dear Warren,

        Prism Solutions, Inc. (the "Company") is pleased to offer you a
position as President and Chief Executive Officer of the Company and a position
on its Board of Directors, on the terms set forth in this letter agreement,
effective as of January 23, 1997 upon your acceptance by execution of a
counterpart copy of this letter where indicated below.

        1. Reporting; Duties and Responsibilities; Employment At Will; Employee
Invention Assignment and Confidentiality Agreement. In this position you will
report to the Board of Directors of the Company. This offer is for a full time
position, located at the offices of the Company, except as travel to other
locations may be necessary to fulfill your responsibilities. Your employment
with the Company is on an "at will" basis, and either you or the Company may
terminate your employment with the Company at any time, for any reason. You
will be required to enter into an Invention Assignment and Confidentiality
Agreement as described in paragraph 5 below. Upon your acceptance of this offer
to become the Company's Chief Executive Officer, the Board of Directors will
elect you to fill a position on the Company's Board of Directors, and while you
remain the Chief Executive Officer of the Company, the Board of Directors will
continue to nominate you for a position on the Board of Directors of the
Company.

        2. Severance Payments Upon Termination. If the Board of Directors
terminates your employment with the Company for any reason other than your
gross misconduct or the acquisition of the Company, the Company will pay you as
agreed upon severance an amount equal to your then base salary for the lesser
of (i) twelve months; or (ii) the number of months of service with Company up
to the termination date. If your employment with the Company is terminated
because the Company is acquired, or if you terminate your employment after an
acquisition of the Company because you are offered a position with the
successor in interest to the Company in which your salary is reduced from that
existing prior to the acquisition or you no longer are responsible for managing
the Company's business, the Company will pay you as agreed upon severance your
then base salary for the lessor of (i) twelve months following such
termination; or (ii) the number of months before you obtain a position with
another firm. In addition, if your employment with the Company is terminated
because the Company is acquired, or if you terminate your employment after an
acquisition of the Company because you are offered a position with the
successor in interest to the Company, the vesting period of all options held by
you will

 
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be accelerated such that all outstanding options will become available for
exercise. If the Company is acquired and you choose not to remain with the
Company at your sole discretion, 50% of your then unvested options will become
available for exercise. You will be granted a period of twelve months to
exercise options in the event of your termination by the Board of Directors. You
agree that the payments set forth in this offer letter constitute all payments
that you shall be entitled to, and under any theory, in the event of any
termination of employment.

        3. Salary; Bonus; Benefits and Vacation. Your initial base salary will
be $20,834.00 per month, subject to adjustment in good faith by the Company's
Board of Directors, payable in accordance with the Company's customary payroll
practice as in effect from time to time. You will be paid a signing bonus of
$50,000 if you commence employment with the Company on or before February 15,
1997. You will also be eligible to earn an annual bonus in the amount of
$100,000 based on the achievement of objectives which you and the Company's
Board of Directors will mutually determine in good faith. The objectives for
1997 will be determined promptly after your acceptance of this letter;
objectives for future years will be determined promptly after the beginning of
each fiscal year of the Company. You will also receive the Company's standard
employee benefits package, and will be subject to the Company's vacation
policy, as such package and policy are in effect from time to time.

        4. Stock Options. Effective at the Company's Board of Directors meeting
next after your acceptance of the offer contained in this letter, the Board will
grant you two stock options, effective upon the date of your commencement of
employment pursuant to this letter agreement. All options will have an exercise
price equal to the then-current fair market value of the Company Common Stock at
the date of grant, such date to be within 15 days of your acceptance of this
letter. If the Company is acquired before your options are fully vested, then
the provisions described in paragraph 2 above will apply. 

        (a)     The first option will be to purchase up to 650,000 shares of
the Company Common Stock pursuant to the Company's Stock Option Plan. The
option will become exercisable over a four-year exercise schedule at the rate
of 13,542 shares per month, at the close of each month during which you remain
employed with the Company. With this provision, the Board is waiving the usual
requirement in the Company's option program which calls for "cliff" vesting of
the first 25% after twelve months of service.

        (b)     The second option will be to purchase up to 50,000 shares of
the Company Common Stock pursuant to the Company's Stock Option Plan. The
option only will become capable of becoming exercisable ("Exercisable") upon
the earlier of (i) the Company's Common Stock having a closing price in excess
of $25.00 per share for more than 30 consecutive trading days; or (ii) eight
years after the date of grant. If such option becomes "Exercisable", its
vesting will be at the rate of 1,042 shares per month, at the close of each
month during which you remain employed with the Company. Again, with this
provision, the board is waiving the usual requirement in the Company's option
program which calls for "cliff" vesting of the first 25% after twelve months of
service. 

        5. Confidential Information. As an employee of the Company, you will
have access to certain Company confidential information and you may, during the
course of your employment, develop certain information or inventions which will
be the property of the Company. To protect the interest of the Company, you
will need to sign the Company's standard "Employee Inventions and
Confidentiality Agreement" as a condition of your employment. We wish to
impress upon you that we do not wish you to bring with you any confidential or
proprietary material of any former employer or to violate any other obligation
to your former employers.
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        6. At-Will Employment. While we look forward to a long and profitable
relationship, should you decide to accept our offer, you will be an at-will
employee of the Company, which means the employment relationship can be
terminated by either of us for any reason at any time. Any statements or
representations to the contrary (and, indeed, any statements contradicting any
provision in this letter) should be regarded by you as ineffective. Further,
your participation in any stock option or benefit program is not to be regarded
as assuring you of continuing employment for any particular period of time.

        7. Authorization to Work. Because of Federal regulations adopted in
the Immigration Reform and Control Act of 1986, you will need to present
documentation demonstrating that you have authorization to work in the United
States. If you have any questions about this requirement, which applies to U.S.
citizens and non-U.S. citizens alike, please contact our human resources
department. 

        8. Term of Offer. This offer will remain open until January 24, 1997.
If you decide to accept our offer, and I hope that you will, please sign the
enclosed copy of this letter in the space indicated and return it to me or to
Kevin Fong. Upon your signature below, this will become our binding agreement
with respect to the subject matter of this letter, superseding in their
entirety all other or prior agreements by you with the Company as to the
specific subjects of this letter, will be binding upon and inure to the benefit
of our respective successors and assigns, and your heirs, administrators and
executors, will be governed by California law, and may only be amended in a
writing signed by you and the Company.

        We are excited to have you join us and look forward to working with
you. We will be required to announce your joining us in a timely manner and
will work on the details of our press announcements with you.


                                Sincerely,
                                
                                /s/ E. FLOYD KVAMME
                                ------------------------------------------
                                E. Floyd Kvamme, Director
                                for the Board of Directors

Acknowledged, Accepted and Agreed               Date:


/s/ WARREN M. WEISS                             1/22/97
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Warren M. Weiss