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                                                                    Exhibit 10.1

                         RELEASE AND SEVERANCE AGREEMENT
                         -------------------------------

     This Release and Severance Agreement ("Agreement") is an agreement between
you, Randy A. Gray (for yourself, your administrators, executors, spouse, heirs,
or assigns, and anyone acting for you) and Click Commerce, Inc., a Delaware
corporation and its directors, officers, associates, employees, partners and
agents, past, present, and future, and each of its and their respective
successors and assigns (collectively, "Click Commerce") effective as of the 30th
day of September, 2001.

1.   Termination of Employment
     -------------------------

     You and Click Commerce have agreed that you will resign from employment
with Click Commerce effective as of September 30, 2001 and that any rights you
may have to compensation or benefits from Click Commerce from and after this
date shall be determined solely under the terms of this Agreement.

     Any benefit continuation or conversion rights existing under any
established plans of Click Commerce in which you participated during your
employment shall be made available to you in accordance with the terms of such
established plans. If you have any questions regarding any benefit continuation
or conversion rights, please contact Rebecca Maskey or such other specifically
designated representative of Click Commerce.

2.   Severance Arrangements
     ----------------------

     In consideration for your agreement not to disclose this Agreement or any
terms hereof and to comply in all respects with all of the terms and conditions
of this Agreement, including, without limitations, those set forth in Section 4
hereof, the terms and conditions of Sections 7, 8 and 9 of the Amended and
Restated Employment Agreement between you and Click Commerce dated as of
February 17, 2000 ("Employment Agreement"), and the terms and conditions of that
certain Employee Confidentiality Agreement between you and Click Commerce
("Employee Confidentiality Agreement"), pursuant to your execution and delivery
of this Agreement, Click Commerce hereby agrees (i) to pay you cash severance in
thirty nine (39) equal bi-weekly installments of $9,615.38 (less applicable
withholding and taxes) commencing after the termination of your employment with
Click Commerce, (ii) to continue to provide the Additional Benefits (as
described in Section 5(b) of the Employment Agreement) through February 28,
2003, and (iii) to continue to provide or make payments on your behalf to
continue the medical benefits pursuant to the Comprehensive Omnibus Budget
Reconciliation Act (COBRA) and the disability, dental and life insurance
benefits set forth in Section 5(a) of the Employment Agreement, commencing
following the termination of your employment and terminating upon the earlier of
(x) February 28, 2003 or (y) your eligibility to receive medical benefits from
another entity (collectively, the "Severance Arrangements"). In addition,
pursuant to the terms of the Employment Agreement, all options to purchase
common stock of Click Commerce ("Options") granted under Section 4(d) shall
become exercisable as of the date of this Agreement and for a period of one year
after September 30, 2001, terminating on September 30, 2002 if not exercised
prior thereto, and you will be paid a lump sum amount in cash equal to $9,615.38
representing two weeks of accrued but unpaid vacation time. During the period
commencing upon the date of your termination of employment through December 31,
2001, you shall be permitted to continue to use, at the Corporation's expense,
the laptop computer and a

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cellular telephone currently in your possession and owned or leased by the
Corporation.

     You acknowledge that the foregoing Severance Arrangements are benefits and
considerations which you would not be entitled to under Click Commerce's
established policies, plans, and procedures and that the Severance Arrangements
are in exchange for your signing (and not later revoking) this Agreement. You
further acknowledge and agree that Click Commerce's offer and provision of the
Severance Arrangements to you and your execution and delivery of this Agreement
does not in any way indicate that you have any viable claims against Click
Commerce or that Click Commerce admits any liability to you whatsoever.

3.   Waiver and Release
     ------------------

     You hereby release Click Commerce with respect to any and all known and
unknown claims of any type to date arising out of any aspect of your employment
or the termination of your employment. This includes, but is not limited to,
breach of any implied or express employment contracts, covenants or duties;
entitlement to any pay or benefits, including insurance benefits or attorney
fees; claims for wrongful termination, violation of public policy, defamation,
emotional distress, invasion of privacy, loss of consortium, negligence, other
federal, state, local or common law matters or any act or omission; or claims of
discrimination based on age (Age Discrimination in Employment Act) ("ADEA"),
ancestry, color, concerted activity, disability, entitlement to benefits,
marital status, national origin, parental status, race, religion, retaliation,
sex, sexual harassment, sexual orientation, source of income, union activity,
veteran's status or other protected status. For purposes of the release of any
ADEA claims, the parties agree that twenty five percent (25%) of the amounts
paid hereunder shall be deemed to be applied for the release of any such ADEA
claims.

     You further agree not to sue Click Commerce for any claims covered by this
Agreement. This agreement not to sue does not apply to an ADEA claim to the
extent such an exception is required by law. If you sue in violation of this
Agreement, you agree (1) to pay all costs and expenses incurred by Click
Commerce in defending against a suit or enforcing this Agreement, including
court costs, expenses and reasonable attorney fees, or (2) to be obligated upon
written demand to repay to Click Commerce as liquidated damages, 50% of the
proceeds from the sale of Click Commerce common stock issued pursuant to the
exercise of the Options and 50% of amounts paid under this Agreement.

     Excluded from the release and the agreement not to sue are any claims which
cannot be waived by law, and the filing of a charge with the Equal Employment
Opportunity Commission. But you agree to waive any right to any monetary
recovery should any government agency pursue any claims on your behalf. You also
acknowledge that you have not suffered any on-the-job injury for which you have
not already filed a claim.

     You further acknowledge and agree in the event that you breach the
provisions of this Agreement, Click Commerce shall (i) be entitled to apply for
and receive an injunction to restrain any violation of this Agreement and (ii)
to immediately cancel any outstanding Options and direct the Secretary or
transfer agent not to recognize any request to exercise such Options, and you
shall be obligated to pay to Click Commerce its costs and expenses in obtaining
such injunction and/or enforcing this Agreement and defending against such
lawsuit (including court costs, expenses and reasonable legal fees) and the
foregoing shall not affect the validity of this Agreement and such relief

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does not constitute in any way a penalty or a forfeiture.

4.   Confidentiality; Non-Disparagement
     ----------------------------------

     You agree that you have not disclosed, and from and after today you will,
keep strictly confidential, the existence and terms of this Agreement and you
further agree that you will not disclose them to any person or entity, other
than to your immediate family, your attorney, and your financial advisor, or
except as may be required by law.

     You further agree that you shall not directly or indirectly, individually
or in concert with others, (1) disparage, interfere with or attempt to interfere
with, Click Commerce's reputation, goodwill, services, business, and/or Click
Commerce's stockholders, directors, officers, employees, agents and its
affiliates, or (2) engage in any conduct, take any actions or make any
statements (oral or written) to the public, future employers, customers,
vendors, the investment community, the media, current, former or future Click
Commerce employees, or any other third party whatsoever, that is calculated to
have, or likely or possibly having, the effect of undermining, disparaging or
otherwise reflecting negatively, or could reasonably be considered to undermine,
disparage or reflect negatively, on Click Commerce, its reputation, goodwill,
services, business, and/or its stockholders, directors, officers, employees,
agents and its affiliates.

     You also acknowledge and agree that you remain bound by those provisions of
your Employee Confidentiality Agreement with Click Commerce which survive your
resignation, including, without limitation, provisions regarding
confidentiality, non-competition, non-solicitation and assignment of invention
contained in such Employee Confidentiality Agreement, a copy of which is
attached hereto and incorporated by reference herein.

     You acknowledge that the provisions of this Section 4 are reasonable and
not unduly restrictive of your rights as an individual and you warrant that as
of the date you sign this Agreement you have not breached any of the provisions
of this Section 4. You further acknowledge and agree that any violation of this
Section 4, without regard to the materiality thereof, shall result in the
immediate and automatic cancellation of the Options, without opportunity to
cure.

5.   Miscellaneous.
     -------------

     This Agreement is deemed made and entered into in the State of Illinois,
and in all respects shall be interpreted, enforced and governed under the
internal laws of the State of Illinois. Any dispute under this Agreement shall
be adjudicated by a court of competent jurisdiction in the State of Illinois.

     This Agreement resolves all matters between you and Click Commerce and
supersedes any other written or oral agreement between you and the Click
Commerce other than the Employment Agreement, the Employee Confidentiality
Agreement (as set forth in Section 4 above), and certain option agreements
between you and Click Commerce. The Severance Arrangements described above
exceeds any amounts that would normally be received by you upon the termination
of your employment with Click Commerce. You agree that you are signing this
Agreement knowingly and voluntarily, that you have not been coerced or
threatened into signing this Agreement and that you have not been promised
anything else in exchange for signing this Agreement. If any part of this

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Agreement is found to be illegal or invalid, the rest of this Agreement will
still be enforceable.

     You further agree that you have been given at least twenty-one (21) days to
consider this Agreement. By this Agreement, you have been advised to consult
with an attorney of your choice at your own expense before signing below. After
you sign this Agreement, you have seven (7) days to revoke it by giving Click
Commerce written notice of your revocation. If you do not revoke this Severance
Agreement, Click Commerce will enter into the Severance Arrangements described
above with you.

     This Agreement has been individually negotiated and is not part of a group
exit incentive or other termination program.

     No modification of any provision of this Agreement shall be effective
unless made in writing and signed by you and Click Commerce.

     IN WITNESS WHEREOF, this Agreement has been executed and agreed to as of
the date first above written.

                                                     /s/ Randy A. Gray
                                            ------------------------------------
                                                      Randy A. Gray

                                            CLICK COMMERCE, INC.



                                            By /s/ Rebecca S. Maskey
                                               ---------------------------------
                                            Its: Executive Vice President, Chief
                                                 -------------------------------
                                                 Financial Officer and Treasurer
                                                 -------------------------------
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