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                                                                   Exhibit 10.15

                                                                October 24, 2001

Jon Niess
14985 Camdon Hill
Eden Prairie, MN 55347

Dear Jon:

     It is with pleasure that I extend this offer of employment to you on behalf
of Click Commerce, Inc. ("Click"). I am confident that with your skills, hard
work and dedication we can significantly grow the Click business to be the
nation's leading Business-to-Business E-Commerce Company.

     This letter sets forth Click's offer of employment to you on the following
terms:

1.   Position: Senior Vice President, Field Operations

2.   Reporting Manager: William Conroy, President and COO

3.   Base Compensation: $225,000 annual salary, currently being paid equally
     over 26 payment periods

4.   Variable Compensation: Beginning January 1, 2002, you will be eligible an
     additional annual cash bonus equal up to $175,000. This annual bonus shall
     be based upon the achievement of specified organizational and personal
     management objectives to be agreed upon and determined by the Corporation's
     senior management team and the Human Resources and Compensation Committee
     of the Board of Directors of the Corporation ("Bonus Objectives") and will
     be paid annually. The remaining portion of the bonus will be based on the
     achievement of quarterly sales goals and will be paid quarterly. The Bonus
     Objectives for a particular calendar year shall be determined not later
     than the commencement of such year, shall be set forth in writing, and
     shall set forth the objectives to be achieved on a quarterly and annual
     basis.

5.   Stock Options: Subject to your execution of a Stock Option Agreement, you
     will be granted options to purchase an aggregate of 400,000 shares of
     common stock at an exercise price equal to the fair market value of Click's
     stock on your start date as determined by the Board of Directors. The
     options shall vest annually on a pro-rata basis over three years.

6.   Acceleration of Option Vesting: In the event of a Change in Control of the
     Corporation, notwithstanding the vesting schedule set forth in Item 5, all
     of the unvested Options shall immediately vest. Should the new controlling
     party so desire, you would be obligated to remain in its employ for twelve
     (12) months from the date of change in control in order to receive the
     immediate vesting outlined in this paragraph.

7.   Start Date: October 30,2001


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8.   Housing: You will have the use of a Click Commerce corporate apartment
     while commuting to Chicago.

9.   Relocation: You agree that no later than July 31, 2002, you will decide to
     relocate your primary residence to Chicago, if requested by the company.
     Such relocation will be completed no later than October 1, 2002. If you
     decide to relocate, you will be paid a moving allowance of $50,000 and you
     will be directly responsible for payment of all of your moving expenses
     from that allowance. If you decide not to relocate, you will terminate your
     employment with the company and you shall become immediately vested in
     66,667 options.

10.  Benefits Summary: You will become eligible on your first day of employment
     for the benefits set forth below:

     -    Medical, dental, and vision insurance
     -    $50,000 of life insurance, short-term and long-term disability
          insurance
     -    Four (4) weeks vacation each calendar year, with the first year's
          accrual prorated to your start date
     -    401K with a Company match after a 6 months of employment

11.  Termination for Reason Other Than Cause: In the event of a termination by
     the Corporation for any reason other than cause, as defined below, the
     Corporation shall be obligated to pay you ninety (90) days base salary in
     bi-weekly installments. In addition, you shall be entitled to keep all
     Options vested pursuant to Item 5 as of the date of termination and you
     shall be entitled to retain such additional Options that would otherwise
     vest within the one year period immediately following such termination
     date.

     Click shall have "Cause" to terminate your employment on the basis of: (i)
     your willful misconduct or gross negligence in connection with the
     performance of your responsibilities and duties for Click. (ii) an act by
     you of fraud, misappropriation or dishonesty that results in or is intended
     to result in your personal enrichment at the expense of Click or any of its
     customers, vendors or suppliers, (iii) your commission of any act that
     constitutes a felony, (iv) your commission of any other crime or offense
     that involves the property, business relationships or employees of Click,
     (v) the breach by you of any obligation of confidentiality,
     non-solicitation, or non-competition under any written agreement with Click
     or any obligation to Click imposed or imputed by applicable law, or (vi)
     exhibited documented habitual absenteeism or repeated failure to perform an
     reasonable or customary task typically required in connection with your
     employment and position with Click or its subsidiaries.

12.  Contingencies: This offer is contingent upon your signing of an Employee
     Confidentiality Agreement. Click reserves the right to withdraw this
     employment offer if not accepted by you within five (5) calendar days of
     the date of this letter or if Click, in its sole and absolute discretion,
     cannot verify any representations made by you (education, experience, prior
     employment).

13.  Employment at Will: This offer of employment does not constitute an
     employment agreement, but sets forth the general terms upon which you will
     be offered employment by Click. Your employment will be "at-will" and both
     Click and you retain the right to terminate the employment relationship at
     any time without cause.

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14.  No Restrictions: By executing this offer, you warrant that you are not
     under any other employment obligations and are not contractually prohibited
     or precluded from accepting an employment offer from Click.

     I want to welcome you to Click and tell you how excited I am for the growth
possibilities that we have at Click. If the above terms are satisfactory, please
sign on the acceptance line and fax it back to (312) 377-7704 (attention Becky
Maskey). If you have any questions regarding this offer please contact me at
(312) 482-9006.

     The undersigned agrees that no representations, warranties, conditions or
agreements, oral or written, express or implied, have been made except as
expressly provided herein. This offer contains the entire terms and conditions
of employment by Click and supersedes and cancels any and all prior or
contemporaneous oral or written understandings, negotiations and agreements.

                                                              Sincerely,
Acceptance:

/s/ Jon O. Niess           October 25, 2001                   William M. Conroy
------------------------------------------------------        President and COO
Jon O. Niess               Date

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