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                                                                   EXHIBIT 10.15


                                 AMENDMENT NO. 1
                                       TO
                       SHARES SALE AND PURCHASE AGREEMENT


Amendment No. 1, dated as of December 31, 2001 (the "Amendment"), to the Shares
Sale and Purchase Agreement dated November 28, 2001 (the "Agreement"), by and
among Image Sensing Systems, Inc., a company incorporated in Minnesota, USA
("ISS"), Berkeley Development Limited, a company incorporated in the British
Virgin Islands ("BDL"), Mr. Mats Johan Billow, a resident of Hong Kong
("Billow"), and Grove Place Limited, a company incorporated in the British
Virgin Islands ("Grove").

         WHEREAS, the parties to this Amendment previously entered into the
Agreement, pursuant to which BDL, Billow and Grove (collectively, the "Vendors")
have agreed to sell, and ISS has agreed to purchase, all of the outstanding
shares, par value HK$1.00 per share, of Flow Traffic Limited, a company
incorporated in Hong Kong, owned by the Vendors; and

         WHEREAS, the parties desire to amend the Agreement in certain respects,
in accordance with Section 9 of the Agreement.

         NOW, THEREFORE, in consideration of the premises and the mutual
agreements herein set forth, the parties hereby agree as follows:

1.       Amendment of the Agreement.  The Agreement shall be amended as follows:

         (a)      Section 5(e) of the Agreement is hereby amended to read in its
                  entirety as follows:

         "US$125,000 of the Billow Consideration shall be payable by ISS in the
         form of a non-interest bearing, non-negotiable note convertible into
         50,000 shares of common stock of ISS, par value US$.01 per share, at
         any time within five years from the date of issuance (the "Billow
         Note"). Billow may demand payment for the Billow Note at any time after
         April 1, 2003; provided that the Billow Note may be prepaid at the
         option of ISS for its face amount at any time during calendar year 2002
         or for US$150,000 at any time after April 1, 2003. If not converted or
         paid by January 7, 2007, the Billow Note will be redeemed by ISS on
         such date for its face amount of US$125,000."

         (b)      Section 5(f) of the Agreement is hereby amended to read in its
                  entirety as follows:

         "US$125,000 of the Grove Consideration shall be payable by ISS in the
         form of a non-interest bearing, non-negotiable note convertible into
         50,000 shares of common stock of ISS, par value US$.01 per share, at
         any time within five years from the date of issuance (the "Grove
         Note"). Grove may demand payment for the Grove Note at any time after
         April 1, 2003; provided that the Grove Note may be prepaid at the
         option of ISS for its face amount at any time during calendar year 2002
         or for US$150,000 at any time after April 1, 2003. If not converted or
         paid by January 7, 2007, the Grove Note will be redeemed by ISS on such
         date for its face amount of US$125,000."

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         2.       Counterparts. This Amendment may be executed in any number of
         counterparts and each of such counterparts shall for all purposes be
         deemed to be an original, and all such counterparts shall together
         constitute but one and the same instrument.

                  IN WITNESS WHEREOF, the parties have caused this Amendment to
         be duly executed as of the date first above written.

                              IMAGE SENSING SYSTEMS, INC.

                              /s/ William L. Russell
                              --------------------------------------------
                              Name:  William L. Russell
                              Title:  Chairman and Chief Executive Officer


                              BERKELEY DEVELOPMENT LIMITED

                              /s/ Johan Billow
                              --------------------------------------------
                              Name:  Johan Billow
                              Title:  Director


                              MR. MATS JOHAN BILLOW

                              /s/ Johan Billow
                              --------------------------------------------


                              GROVE PLACE LIMITED


                              /s/ Anthony H. Gould
                              --------------------------------------------
                              Name:  Anthony H. Gould
                                     Title: