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                     LOCK-UP AND MARKET-OUT LETTER AGREEMENT


The Board of Directors
U.S. Interactive, Inc.
2012 Renaissance Boulevard
King of Prussia, PA 19406

Ladies and Gentlemen:

         In connection with the merger of Soft Plus, Inc., a California
corporation and First Acquisition Co., a Delaware corporation and a wholly owned
subsidiary of U.S. Interactive, Inc., a Delaware corporation ("USI"), pursuant
to a certain Agreement and Plan of Merger dated February 1, 2000 (the "Merger
Agreement"), the undersigned has received _________________________ unregistered
shares of USI Common Stock, par value $0.001 per share (the "Shares").

1.       In consideration of the execution of the Merger Agreement, and for
         other good and valuable consideration, the undersigned hereby
         irrevocably agrees that, without the prior written consent of USI, the
         undersigned will not, directly or indirectly, (1) offer for sale, sell,
         pledge, or otherwise dispose of (or enter into any transaction or
         device that is designed to, or could be expected to, result in the
         disposition by any person at any time in the future of) any Shares
         (including, without limitation, Shares that may be deemed to be
         beneficially owned by the undersigned in accordance with the rules and
         regulations of the Securities and Exchange Commission), or securities
         convertible into or exchangeable for shares of USI Common Stock
         (collectively, the "Restricted Securities"), owned by the undersigned
         in connection with the closing of the Merger Agreement, or (2) enter
         into any swap or other derivatives transaction that transfers to
         another, in whole or in part, any of the economic benefits or risks of
         ownership of such Restricted Securities, whether any such transaction
         described in clause (1) or (2) above is to be settled by delivery of
         Common Stock or other securities, in cash or otherwise, for a period of
         24 months after the closing date of the transaction contemplated by the
         Merger Agreement. The foregoing shall also apply to Restricted
         Securities that are registered by USI from time to time as contemplated
         in the Merger Agreement but not otherwise sold pursuant to the terms of
         the Merger Agreement.

2.       The foregoing restriction shall lapse with respect to one-quarter of
         the Restricted Securities every six months beginning on a date six
         months following the closing date of the transaction contemplated by
         the Merger Agreement, resulting in the restriction on the disposition
         of the Restricted Securities described in Paragraph 1 above to lapse
         with respect to 100% of the Restricted Securities owned or beneficially
         owned by the undersigned on the second anniversary of the closing date
         of the transaction contemplated by the Merger Agreement.

3.       The undersigned further agrees that, upon the request of USI's
         underwriters in the event USI becomes engaged in a firmly underwritten
         public offering of its Common Stock following the date hereof, any
         Restricted Securities owned or beneficially owned by the undersigned
         shall be or become subject to the restrictions on disposition described
         in Paragraph 1 for a period of time requested by such underwriters from
         the effective date of any such public offering (not to exceed six
         months) (regardless of whether such restrictions have lapsed with
         respect to any of the Restricted Securities as provided in Paragraph 2
         above); provided, however, that the obligations under this Section 3
         are conditioned upon each of the officers, directors and 1%
         shareholders of USI selling in such offering entering into and
         remaining subject to similar agreements with substantially the same
         restrictions.

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4.       Notwithstanding the foregoing the undersigned may make gifts of
         Restricted Securities or other securities convertible into, or
         exchangeable or exercisable for, Restricted Securities or other
         derivatives during the above-referenced lock-up and market out periods
         if the donee agrees in writing to be bound by the terms of this
         agreement for the remainder of the lock-up and market out periods.

5.       In furtherance of the foregoing, the certificate representing the
         Restricted Securities issued to me will contain a restrictive legend
         pertaining to the above limitations on resale and that transfer
         instructions will be noted on the Company's stock transfer ledger with
         respect to the Restricted Securities. USI and its Transfer Agent are
         hereby authorized to decline to make any transfer of securities if such
         transfer would constitute a violation or breach of this Lock-Up and
         Market-Out Letter Agreement.

6.       The undersigned understands that execution of this Lock-Up and
         Market-Out Letter Agreement is a condition to closing of the
         transaction contemplated by the Merger Agreement.

         The undersigned hereby represents and warrants that the undersigned has
full power and authority to enter into this Lock-Up and Market-Out Letter
Agreement. Any obligations of the undersigned shall be binding upon the heirs,
personal representatives, successors and assigns of the undersigned.


                                           Very truly yours,


                                           ____________________________________



Date:  _______________