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                                                           Exhibit 4.15

                                                      December 12, 1999

Robert Shaw
c/o USWeb Corporation
410 Townsend Street
San Francisco, CA 94107

Dear Robert:

     Reference is made to (a) the Employment Agreement, between you and USWeb
Corporation, a Delaware corporation (the "Company"), dated as of November 1,
1998 (the "Employment Agreement"), and (b) the Agreement and Plan of Merger,
dated December 12, 1999 (together with any amendments thereto, the "Merger
Agreement"), by and among Whittman-Hart, Inc., a Delaware corporation
("Parent"), the Company and Uniwhale, Inc., a Delaware corporation and a
wholly owned subsidiary of Parent ("Merger Sub"), pursuant to which Merger
Sub will be merged with and into the Company, with the Company continuing as
the surviving corporation and as a direct wholly-owned subsidiary of Parent
(the "Merger"). This letter constitutes the undertakings of you and the
Company in connection with the Merger Agreement.  Capitalized terms used in
this letter without definition shall have the meanings assigned to them in
the Employment Agreement.

     In order to facilitate the Merger, you and the Company hereby amend the
terms of the Employment Agreement as follows:

     1.   You acknowledge and agree that, for the purposes of Section 8(a) of
          the Employment Agreement, the Merger shall not constitute a Change
          of Control under the Employment Agreement. By signing this letter
          below, you hereby waive any right to make such claim. All other
          terms and conditions of the Employment Agreement shall remain in
          full force and effect, including without limitation, (i) the
          agreement of the Company to provide payments with respect to the
          280G excise tax, including any taxes incurred with respect to the
          Merger, pursuant to Section 8(b) of the Employment Agreement and
          (ii) any other severance benefit provisions not specifically
          related to a Change of Control, including pursuant to Sections 7(a)
          and (b) of the Employment Agreement.

     2.   Any options to purchase shares of common stock of the Company held
          by you that are not currently exercisable as of the date hereof
          (together with any options to purchase shares of common stock of
          Parent received in exchange for such options in connection with the
          Merger, the "Unvested Options") shall become exercisable according
          to the following schedule:

          (a)    From the date hereof until the Closing Date, the Unvested
                 Options shall continue to vest and become exercisable
                 according to the original

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                 schedule of 1/48th of 1,200,000 shares per month as set
                 forth in the Employment Agreement;

          (b)    On the Closing Date, Unvested Options for the additional
                 number of shares of common stock that equal the product of
                 (x) 1,200,000 times (y) the fraction, the numerator of which
                 is the number of full months that have elapsed between the
                 November 1, 1998 and the Closing Date, and the denominator
                 of which is 48, shall vest and become immediately
                 exercisable; and

          (c)    After the Closing Date, any remaining Unvested Options shall
                 vest and become exercisable at the rate of 1/12th of the
                 remaining Unvested Options per month;

PROVIDED, HOWEVER, that the Unvested Options scheduled to become exercisable
on any particular date set forth above shall only become exercisable if you
are an employee, director or consultant of the Company or Parent (or any
affiliate thereof) on such date.

     In the event that the Merger Agreement is terminated for any reason, the
Unvested Options shall be treated as if they had continued to vest on the
schedule contemplated by the Employment Agreement and your option
agreement(s) with the Company.

     This agreement shall be binding on your successors and assigns,
including heirs, executors and administrators.

     You hereby acknowledge that the execution of this letter agreement is an
inducement to Parent and the Company to enter into the Merger Agreement and
that you understand the rights and obligations of this letter and the effects
of such letter on the Unvested Options.

                              Sincerely,


                              USWEB CORPORATION


                              By: _____________________________________________
                                  Name:  Carolyn Aver
                                  Title: Chief Financial Officer


AGREED AND ACKNOWLEDGED BY:

/s/ Robert Shaw
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Robert Shaw