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                                                                    EXHIBIT 2.3a

                                 AMENDMENT NO. 1
                                     TO THE
                  AMENDED AND RESTATED STOCK PURCHASE AGREEMENT

         This AMENDMENT NO. 1 TO THE AMENDED AND RESTATED STOCK PURCHASE
AGREEMENT (the "Agreement"), dated as of April 30, 1998, is made as of May 27,
1998 by and among SUPERSHUTTLE INTERNATIONAL, INC., a Delaware corporation
("SuperShuttle"); AAA WHEELCHAIR WAGON SERVICES, INC., a Florida corporation
("AAA"); WHEELCHAIR AMBULANCE OF HOLLYWOOD, INC., a Florida corporation
("Wheelchair Ambulance"); LIMOUSINES OF SOUTH FLORIDA, INC., a Florida
corporation ("LSF"); A1A SNOWBIRD LEASING, INC., a Florida corporation
("Snowbird"); and Karen Caputo (the "Shareholder").

         Section 5.2(a) of the Agreement is hereby amended and restated in its
entirety as follows:

         (a) The Share Exchange shall be rescinded automatically without further
         notice (the "Recision") upon the occurrence of any of the following
         events: (i) if SuperShuttle does not file a registration statement for
         an initial public offering on Form S-1 with the SEC by June 8, 1998 to
         register for sale shares of SuperShuttle Common Stock; (ii) if the SEC
         does not declare such registration statement effective by July 31,
         1998; or (iii) if the underwritten initial registration statement for
         an initial public offering on a firm commitment basis does not close by
         August 10, 1998, providing a per share offering price to the public of
         at least $6.50.

IN WITNESS WHEREOF, SuperShuttle, AAA, Wheelchair Ambulance, LSF, Snowbird and
the Shareholder have caused this Amendment No. 1 to be executed on the date
first written above by their respective officers thereunder duly authorized.

                                 SUPERSHUTTLE INTERNATIONAL, INC.,
                                  a Delaware corporation

                                 By: /s/ Thomas C. LaVoy
                                    --------------------------------------------
                                   Thomas C. LaVoy, Chief Financial Officer

                                 AAA WHEELCHAIR WAGON SERVICES,
                                  INC., a Florida corporation

                                 By: /s/ Karen Caputo
                                    --------------------------------------------
                                   Karen Caputo, President
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                                 WHEELCHAIR AMBULANCE OF
                                  HOLLYWOOD, INC., a Florida corporation

                                 By: /s/ Karen Caputo
                                    --------------------------------------------
                                   Karen Caputo, President

                                 LIMOUSINES OF SOUTH FLORIDA, INC.,
                                  a Florida corporation

                                 By: /s/ Karen Caputo
                                    --------------------------------------------
                                   Karen Caputo, President

                                 A1A SNOWBIRD LEASING, INC.,
                                  a Florida corporation

                                 By: /s/ Karen Caputo
                                    --------------------------------------------
                                   Karen Caputo, President

                                 SHAREHOLDER

                                  /s/ Karen Caputo
                                 -----------------------------------------------
                                 Karen Caputo