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                                                                   Exhibit 10.18


                                October 21, 1998

Robert A. Spinner
287 Cross Road
Alamo, CA  94507

Bob:

     This letter of agreement ("Agreement") is to confirm the agreement between
you and Clarify Inc. ("Clarify"") with respect to your transition to part-time
employment status and your eventual separation from Clarify.

     1.   Your full-time employment with Clarify as its Senior Vice President,
Worldwide Sales and company officer will continue through January 1, 1999.
During this period, you will continue your full-time commitment and leadership
of the Clarify sales team with the specific goal and focus of (a) exceeding the
1998 Q4 sales bookings objective, and (b) successfully completing all pre-1999
sales planning activities.

     2.   To provide you with an enhanced incentive to exceed the 1998 Q4 sales
bookings objective, Clarify will provide you with an additional five percent
(5%) commission for all license and first-year maintenance orders booked by
Clarify from October 1, 1998, though December 28, 1998, which exceed Forty
Million Dollars ($40M). In order to be considered a "booked order", eligible
orders must include all of the following: (i) Software License (for new orders)
signed by customer and Clarify, (ii) a completed Exhibit A, (iii) a signed
purchase order or equivalent, (iv) a completed Sales Order Form, and (v) a
completed Win/Loss Report (for new orders). All such transactions must be
eligible for 1998 revenue. Such eligibility will be determined by Clarify's CFO.

     3.   Effective January 2, 1999, you will cease to be an officer of Clarify.
Effective on this date, and continuing through January 1, 2000 or your
Separation Date, whichever is earlier, you will be re-assigned to the part-time
position of Major Accounts Strategist for Clarify, responsible for leveraging
existing major account relationships in order to increase the volume of business
from these strategic customers in 1999. As a part-time employee, you will be
expected to work a maximum of twenty (20) hours per week, and may do so on a
telecommuting basis, as mutually agreed by the parties. Commensurate with your
reduced hours and change in responsibilities, effective January 2, 1999, and
continuing through January 1, 2000, or your Separation Date, whichever is
earlier, you will be paid your salary at the rate of one-half of your current
annual base salary, which is $3,461.54 per pay period, less applicable
withholdings and deductions, according to normal Clarify payroll practices. This
will be your sole compensation during this period, and you will not receive any
additional compensation, including but not limited to, incentives, bonuses,
commissions, allowances or other reimbursements. Because you need not report to
work on a full time basis, you understand and agree that beginning January 2,
1999, you will cease accruing vacation and sick time, and you will be deemed to
have fully used all such accrued but unused vacation and/or sick time during
1999. During this period, you will continue

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Mr. Robert Spinner                                              October 21, 1998
                                                                          Page 2


to be eligible for all other employee benefits, including continued vesting of
your stock options, as well as medical coverage for yourself and your
dependents.

     4.   During your employment with Clarify, you agree to actively
participate, as reasonably required and/or requested by Clarify's CEO, in
effectively transitioning and fully integrating your new replacement into
Clarify's sales organization.

     5.   Nothing in this Agreement shall be construed so as to impair the right
of Clarify to terminate your employment for Cause. "Cause" includes, but is not
limited to, (i) unauthorized use or disclosure of the confidential information
or trade secrets of Clarify, (ii) engaging in competitive activities or working
in any manner with any Clarify Competitors, as defined in Section 12 below,
(iii) violating any other provision of this Agreement, or any provision of the
Proprietary Information and Inventions Agreement, (iv) engaging in any act of
willful misconduct or conviction of a felony, or (v) continued failure to
perform the duties incidental to your employment consistent with this Agreement,
or such duties as reasonably requested by Clarify's CEO. In the event of a
termination of your employment for Cause, you will no longer be entitled to any
further compensation, stock option vesting and/or benefits as of the termination
date.

     6.   Your employment with Clarify will terminate effective January 1, 2000,
or earlier date if you elect to terminate voluntarily or if you are terminated
for Cause as defined above (the "Separation Date"). After that date, you agree
and understand that you will have no right to employment with Clarify and
Clarify shall have no obligation to employ you. On the Separation Date, you will
be paid your remaining salary and you will no longer be entitled to any employee
benefits or continued vesting of your shares. After that date, you will be
eligible for COBRA benefits.

     7.   As of the date of this letter, you hold the following options to
purchase shares of Clarify common stock: an Incentive Stock Option (ISO) granted
on December 14, 1994, for 166,666 shares at an exercise price of $0.2250 per
share; an ISO granted on September 7, 1995, for 33,332 shares at an exercise
price of $3.5625 per share; a Non Qualified (NQ) stock option granted on April
21, 1997 for 43,126 shares at an exercise price of $7.0000 per share; an ISO
granted on April 21, 1997, for 6,874 shares at an option price of $7.0000 per
share; an ISO granted May 9, 1997, for 20,971 shares at an exercise price of
$13.5000 per share; a NQ stock option granted on May 9, 1997, for 1,529 shares
at an exercise price of $13.5000 per share; a NQ stock option granted on
December 22, 1997 for 30,000 shares at an exercise price of $11.0625 per share,
(collectively, the "Options"). Your Options will continue to become exercisable
in accordance with the exercise schedule specified in the stock option
agreements evidencing the Options until your Separation Date. In addition, you
hold shares under an Employee Stock Purchase Plan (ESPP) with an offering date
of November 3, 1995, containing 6,000 unsold shares, and an ESPP with an
offering date of May 1, 1997, containing 2,940 unsold shares. You acknowledge
that you have no other stock rights in Clarify (or any parent or subsidiary)
other than those rights enumerated in this paragraph and all the terms,
conditions and limitations applicable to the Options pursuant to your stock
option agreements and Clarify's applicable Stock 

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Mr. Robert Spinner                                              October 21, 1998
                                                                          Page 3


Option/Stock Issuance Plan shall remain in full force and effect. You further
acknowledge that the exercise of your Options will be subject to satisfaction of
all applicable income and employment taxes. You further acknowledge that you
will be subject to the officer trading "black out" period, which will be in
effect at the time you cease to be an officer of Clarify, and which will
continue in effect until Clarify announces its 1998 fourth quarter revenues.
Thereafter, you will not be subject to any further trading "black out" period
restrictions.

     8.   Clarify acknowledges that you are entitled to the right of
indemnification if, by reason of your prior status as a Clarify officer, you are
threatened to or actually become a party to a lawsuit, in accordance with the
terms of your Indemnification Agreement, attached and incorporated hereto as
Exhibit "A".

     9.   In consideration of the mutual promises and other good and valuable
consideration, the receipt of which is hereby acknowledged by the parties,
Clarify and you agree to fully and forever release and discharge the other party
from any claims and damages and causes of action. Both parties further covenant
not to sue or otherwise institute or cause to be instituted or in any way
participate in legal or administrative proceedings against the other party,
including any and all liabilities, claims, demands, contracts, debts,
obligations and causes of action of every nature, kind and description, in law,
equity, or otherwise, whether or not now known or ascertained, which heretofore
do or may exist. You further agree to waive and release and promise never to
assert any claims or causes of action, whether or not now known, against Clarify
Inc. or its predecessors, successors, subsidiaries, officers, directors, agents,
employees and assigns, with respect to any matter arising out of or connected
with your employment with Clarify or your separation from that employment,
including without limitation, claims of wrongful discharge, breach of contract,
any claims of discrimination based on sex, age, race, national origin, or on any
other basis, under Title VII of the Civil Rights Act of 1964, as amended, the
California Fair Employment and Housing Act, Age Discrimination in Employment Act
of 1967 as amended by the Older Worker Benefit Protection Act, the Americans
with Disabilities Act, and all other local, state or federal laws and
regulations relating to employment.

     10.  Clarify and you expressly waive and release any and all rights and
benefits under Section 1542 of the Civil Code of the State of California, or any
analogous law of any other state, which reads as follows: "A general release
does not extend to claims which the creditor does not know or suspect to exist
in his favor at the time of executing the release, which, if known by him, must
have materially affected his settlement with the debtor."

     11.  You agree that you will maintain the existence of this Agreement, and
any terms and conditions thereof, in the strictest confidence. This obligation
will become effective immediately and shall survive the termination or
expiration of the Agreement. Except for necessary disclosures to your immediate
family, legal and accounting advisors, the timing and content of any and all
communications regarding this matter, both internal and external, must be
coordinated and pre-approved by the CEO.

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Mr. Robert Spinner                                              October 21, 1998
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     12.  During your employment with Clarify, you had and will have access to
trade secrets, and/or information of a confidential or proprietary nature
related to the present or future business of Clarify, and its research and
development. For purposes of clarification, a "trade secret" may consist of any
formula, pattern, device or compilation of information (lists, reports, etc.)
used in business and which gives the business an opportunity to obtain an
advantage over competitors who do not know or use this. You agree that you shall
not disclose Clarify's trade secrets, or confidential and proprietary
information, directly or indirectly, or use them in any way. This obligation
will survive the expiration or termination of this Agreement, or any employment
relationship with Clarify. Furthermore, you acknowledge that you are bound by
the obligations contained in your Proprietary Information and Inventions
Agreement, attached and incorporated hereto as Exhibit "B".

     13.  You agree that you will not engage in any activity that would be
competitive with the business of Clarify. For purposes of clarification, the
business of Clarify currently consists of front office management applications
and support, such as field logistics, service management, call center
management, and sales force automation. ("Applications"). Furthermore, you agree
not to work for, consult, or be affiliated in any manner with any companies,
which are deemed competitive to Clarify ("Competitor/s"). Currently the
Competitors list includes Seibel, Vantive, Oracle, SAP, BAAN, PeopleSoft, J.D.
Edwards, Onyx and Pivotal, and any of their successors or affiliates. This
obligation shall remain in effect through January 1, 2000. Up until that date,
Clarify may reasonably add other companies to the Competitors list. You agree
that if there is any doubt or question whatsoever concerning the applicability
of this provision to any contemplated employment, consulting or business venture
opportunity you are seeking, that you will promptly contact Clarify's CEO for
advance approval.

     14.  You agree that all customers of Clarify, which you have solicited,
worked with, and serviced, as well as all prospective customers from whom you
solicited business while in Clarify's employ, shall be solely customers of
Clarify. You agree that you will not induce or attempt to induce any customer
(for those Applications), supplier, licensee or licensor or other business
relation of Clarify, either directly or indirectly, to cease doing business with
Clarify, or in any way interfere with the relationship between such customer,
supplier, licensee, licensor or business relation and Clarify. This obligation
shall remain in effect through January 1, 2000.

     15.  You agree not to, either directly or indirectly, approach, solicit or
encourage any Clarify employee, consultant or contractor to work for any Clarify
Competitor, or to leave Clarify for any reason whatsoever. This obligation shall
remain in effect through January 1, 2000.

     16.  You agree that you will not make any derogatory or disparaging remarks
about Clarify, or its products, business practices, officers, directors or
employees at any time in the future. The officers and directors of Clarify also
agree that they will not make any derogatory or disparaging remarks about you.
You will direct any requests for employment references to Clarify's Vice
President of Human Resources. This obligation will survive the expiration or
termination of this Agreement, or any employment relationship with Clarify.

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Mr. Robert Spinner                                              October 21, 1998
                                                                          Page 5


     17.  Clarify and you agree that this Agreement, along with any Exhibits
attached hereto and incorporated herein by reference, constitutes the entire
agreement between you and Clarify with respect to any matters referred to
herein. This Agreement supersedes any and all other agreements, written or
verbal, between you and Clarify, except that you understand and agree that this
Agreement explicitly incorporates by reference all of the terms of Clarify's
Proprietary Information and Invention Agreement executed by you. No other
consideration, agreements, or representations which are not expressly set forth
in this agreement should be implied or are binding. Both parties further agree
that this Agreement shall not be deemed or construed at any time or for any
purposes as an admission of any liability or wrongdoing by either you or
Clarify.

     18.  Any controversy involving the construction or application of any
terms, covenants or conditions of this agreement, or any claims arising out of
or relating to this agreement or the breach thereof will be governed by the
Federal Arbitration Act and submitted to and settled by final and binding
arbitration in Santa Clara County, California. This agreement will be
interpreted under California Law.

     19.  The parties agree that in the event that any provisions herein are
determined by a court of competent jurisdiction to be illegal or invalid such
provisions of this Agreement which are enforceable shall be enforced. Further,
any modifications or amendments hereto may be made only based on written
agreement between you and Clarify's CEO.

     20.  Bob, pursuant to federal law, you have up to twenty-one (21) days
after receipt of this Agreement within which to review it, and to discuss it
with an attorney of your own choosing regarding whether or not you wish to
execute it. Furthermore, you have seven (7) days after you have signed this
letter during which time you may revoke this Agreement.

     21.  If you wish to revoke this Agreement, you may do so by delivering a
letter of revocation to Clarify's CEO. Because of this revocation period, you
understand that the agreement set forth in this letter shall not become
effective or enforceable until the eighth day after the date you sign this
letter.

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Mr. Robert Spinner                                              October 21, 1998
                                                                          Page 6


     Please indicate your agreement with the above terms by signing below.

                                       Sincerely,


                                       /s/ TONY ZINGALE
                                       -----------------------------
                                       Tony Zingale

     My agreement with the above terms is signified by my signature below.
Furthermore, I acknowledge that I have read and understand the foregoing letter
and that I sign this release of all claims voluntarily, with full appreciation
that I am forever foreclosed from pursuing any of the rights I have waived.


Signed: /s/ ROBERT A. SPINNER                Dated: November  4, 1998
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            Robert A. Spinner