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                                                                     Exhibit 4.6

                                ESCROW AGREEMENT


       ESCROW AGREEMENT ("Escrow Agreement"), dated as of this 31st day of
March, 1998, by and among (i) SuperShuttle International, Inc., a Delaware
corporation ("SuperShuttle"); (ii) SuperShuttle Acquisition Co. I, an Arizona
corporation ("Merger Sub"); (iii) Preferred Transportation, Inc., a California
corporation ("PTI"), (iv) Steve Allan and Dave Koscielak (the "Shareholders")
and (v) Robert Splinter (the "Escrow Agent").

                               W I T N E S S E T H

       WHEREAS, (i) SuperShuttle, Merger Sub, PTI and the Shareholders are
parties to a certain Amended and Restated Agreement and Plan of Reorganization
and Merger (the "Merger Agreement"), pursuant to which SuperShuttle is acquiring
all of the outstanding capital stock of PTI (the "PTI Shares") in consideration
for, among other things, shares of common stock of SuperShuttle (the
"SuperShuttle Shares");

       WHEREAS, the PTI Shares and the SuperShuttle Shares are to be placed in
escrow with the Escrow Agent to secure the rights of the parties in accordance
with the terms of the Merger Agreement, and the PTI Shares and the SuperShuttle
Shares are to be released in accordance with the terms and conditions of this
Escrow Agreement; and

       WHEREAS, SuperShuttle, Merger Sub, PTI and the Shareholders are desirous
of having the Escrow Agent serve as the escrow agent for the PTI Shares and the
SuperShuttle Shares, and the Escrow Agent is desirous of serving in such
capacity, in accordance with the terms and conditions contained hereinafter.

       NOW, THEREFORE, in consideration of the mutual premises set forth herein,
and for other good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, the parties hereto hereby agree as follows:

       1.     Establishment and Termination of Escrow. The parties hereto hereby
agree that the PTI Shares will be delivered by the Shareholders and the
SuperShuttle Shares will be delivered by SuperShuttle to the Escrow Agent in
accordance with the terms and conditions of the Merger Agreement, and the Escrow
Agent shall hold said PTI Shares and SuperShuttle Shares in accordance with the
terms and conditions set forth hereinafter. The Escrow Agent is hereby appointed
escrow agent for the purpose of receiving the PTI Shares and the SuperShuttle
Shares. This Escrow Agreement shall automatically terminate in accordance with
its terms upon the release of all of the PTI Shares and the SuperShuttle Shares
from escrow as provided herein.

       2.     Release of Shares.

              A.     The PTI Shares shall be released as follows:

                     (i)    to the Shareholders, in accordance with the terms
              and conditions set forth in the Merger Agreement and Schedule A
              attached hereto, if
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              SuperShuttle does not consummate an initial public offering of
              SuperShuttle Common Stock within 130 days after the date of this
              Agreement, and the Shareholders exercise their right to
              repurchase, at fair market value, the PTI Common Stock transferred
              to SuperShuttle;

                     (ii)   if PTI exercises the repurchase right set forth in
              A(i) above, then the SuperShuttle Shares shall be released to
              SuperShuttle.

              B.     The SuperShuttle Shares shall be released as follows:

                     (i)    to SuperShuttle, in accordance with the terms and
              conditions of the Merger Agreement, (a) if PTI fails to obtain, by
              July 31, 1998, the written approval, acceptable to SuperShuttle,
              of the California Public Utilities Commission to the change in
              ownership of PTI to SuperShuttle; or (b) if PTI fails to obtain,
              by July 31, 1998, all consents necessary by reason of any change
              of control provisions in any license, permit or third party
              contract material to the business of PTI, and SuperShuttle
              exercises its right within thirty (30) days following the
              applicable target date referenced herein to repurchase, at fair
              market value, the SuperShuttle Common Stock transferred to PTI;

                     (ii)   if SuperShuttle exercises the repurchase right set
              forth in B(i) above, then the PTI Shares shall be released to PTI.

              C.     If the Shareholders do not exercise the repurchase right
       set forth in A(i) in accordance with any of the applicable target dates
       set forth therein, and SuperShuttle does not exercise the repurchase
       right set forth in B(i) in accordance with the applicable target date set
       forth therein, then the PTI Shares shall be released to SuperShuttle and
       the SuperShuttle Shares shall be released to PTI.

       3.     Rights, Duties and Responsibilities of Escrow Agent. The parties
hereto hereby acknowledge and agree that the duties of the Escrow Agent
hereunder are purely ministerial in nature. The parties hereto further agree
that:

              A.     During the term of the Escrow Agreement, the Escrow Agent
       shall vote the SuperShuttle Shares as directed by the Shareholders and
       shall vote the PTI Shares as directed by SuperShuttle.

              B.     The Escrow Agent shall not be responsible for the
       performance by any party of its respective obligations under the Merger
       Agreement.

              C.     The Escrow Agent shall have the right to act in reliance
       upon any document, instrument or signature reasonably believed by it to
       be genuine and to assume that any person purporting to give any notice or
       instructions in accordance with this Escrow Agreement or in connection
       with any transaction to which this Escrow Agreement relates has been duly
       authorized to do so.


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              D.     In the event that the Escrow Agent shall be uncertain as to
       its duties or rights hereunder or shall receive instructions with respect
       to the PTI Shares or the SuperShuttle Shares, which, in its sole opinion,
       are in conflict with either other instructions received by it or any
       provision of this Escrow Agreement, it shall be entitled to hold the PTI
       Shares or the SuperShuttle Shares, in escrow, pending the resolution of
       such uncertainty to the Escrow Agent's sole satisfaction, by written
       confirmation of an agreement among SuperShuttle, PTI and the
       Shareholders, or by final judgment of a court or courts of competent
       jurisdiction; or the Escrow Agent, at its option, may deposit the
       SuperShuttle Shares or the PTI Shares, into the registry of a United
       States court of competent jurisdiction in a proceeding to which all
       parties in interest are joined. Notwithstanding anything contained herein
       to the contrary, in the event of any dispute among the parties hereto,
       the parties hereto hereby agree that the Escrow Agent shall not be deemed
       to have a conflict with the representation of PTI and the Shareholders.

       4.     Amendment; Resignation. This Escrow Agreement may be modified or
amended only in writing and with the written consent of all of the parties
hereto. Should the parties herein attempt to change this Escrow Agreement in a
manner which, in the Escrow Agent's sole opinion, is undesirable, the Escrow
Agent may resign as Escrow Agent upon three days' written notice to the other
parties hereto; otherwise, it may resign as Escrow Agent at any time upon five
days' written notice to the parties hereto. In the case of the Escrow Agent's
resignation its only duty shall be to hold and dispose of the SuperShuttle
Shares and the PTI Shares in accordance with the original provisions of this
Escrow Agreement until a successor escrow agent shall be appointed and written
notice of the name and address of such successor escrow agent shall be given to
the Escrow Agent by SuperShuttle and/or PTI and the Shareholders; whereupon the
Escrow Agent's only duty shall be to deliver to the successor escrow agent the
SuperShuttle Shares and the PTI Shares. Any successor escrow agent shall be
appointed hereunder by SuperShuttle subject to the approval of the Shareholders,
which approval shall not be unreasonably withheld.

       5.     Expenses. The Escrow Agent shall be reimbursed by SuperShuttle and
the Shareholders for any and all reasonable expenses incurred in connection with
this Escrow Agreement. Any expenses to be reimbursed hereunder shall be due and
payable upon receipt of an invoice describing the same.

       6.     Indemnification. SuperShuttle, PTI and the Shareholders (the
"Indemnitors"), hereby agree to indemnify, jointly and severally, the Escrow
Agent against, and hold it harmless of and from, any and all loss, liability,
cost, damage and expense, including, without limitation, reasonable legal
counsel fees and court costs, which the Escrow Agent may suffer or incur by
reason of any action, claim, investigation, or proceeding brought against the
Escrow Agent, arising out of or relating in any way to this Escrow Agreement or
any transaction to which this Escrow Agreement related, other than any action,
claim or proceeding resulting from the gross negligence or willful misconduct of
the Escrow Agent. The indemnification provisions herein shall survive the
termination of this Escrow Agreement. SuperShuttle, PTI and the Shareholders,
further agree hereunder that in the event of any required indemnification
hereunder of the Escrow Agent, in the event said indemnification is the result
of any action or claim


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brought or asserted by either SuperShuttle, PTI or the Shareholders, the
prevailing party (either SuperShuttle, PTI and/or the Shareholders) shall be
entitled to be reimbursed in full for any damages or loss suffered as a result
of this indemnification provision and as a consequence of the other party hereto
(either SuperShuttle, PTI and/or the Shareholders) bringing such action or
asserting such claim against the Escrow Agent.

       7.   Miscellaneous.

            A. No Waiver. Neither the failure nor any delay on the part of any
       party to exercise any right, remedy, power or privilege under this Escrow
       Agreement shall operate as a waiver thereof, nor shall any single or
       partial exercise of any right, remedy, power or privilege preclude any
       other or further exercise of the same or of any other right, remedy,
       power or privilege, nor shall any waiver of any right, remedy, power or
       privilege with respect to any occurrence be construed as a waiver of such
       right, remedy, power or privilege with respect to any other occurrence.
       No waiver shall be effective unless it is in writing and is signed by the
       party asserted to have granted such waiver.

            B. Controlling Law. This Escrow Agreement shall be governed by the
       laws of the State of Arizona, without regard to the principles of
       conflict of laws thereof.

            C. Notices. All notices, requests, demands and other communications
       required or permitted under this Escrow Agreement shall be in writing and
       shall be deemed to have been duly given, made and received only when
       personally delivered, on the day received by certified mail, return
       receipt requested or by overnight courier, as evidenced by the signature
       on any receipt with respect to the foregoing, addressed to the addresses
       set forth below, unless notice of a change in address was previously
       given as aforesaid.

            If to SuperShuttle:     SuperShuttle International, Inc.
                                    4610 South 35th Street
                                    Phoenix, Arizona  85040
                                    FAX:  (602) 243-6446
                                    Attn: R. Brian Wier, President and CEO

            With a copy to:         Squire, Sanders & Dempsey L.L.P.
                                    Two Renaissance Square
                                    40 North Central Avenue, Suite 2700
                                    Phoenix, Arizona  85004-4441
                                    FAX:  (602) 253-8129
                                    Attn: Christopher D. Johnson, Esq.


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            If to PTI or
            the Shareholders:       Preferred Transportation, Inc.
                                    1430 South Anaheim
                                    Anaheim, CA  92805
                                    Attn:  Steve Allan

            With a copy to:         Petillon & Hansen
                                    1260 Union Bank Tower
                                    21515 Hawthorne Boulevard
                                    Torrance, CA  90503
                                    Attn:  Ray Seto


              D. Binding Nature of Agreement; No Assignment. This Escrow
       Agreement shall be binding upon and inure to the benefit of the parties
       hereto and their respective heirs, personal representatives, successors
       and assigns, except that no party may assign or transfer its rights under
       this Agreement without the prior written consent of the other parties
       hereto.

              E. Provisions Separable. The provisions of this Escrow Agreement
       are independent of and separable from each other, and no provision shall
       be affected or rendered invalid or unenforceable by virtue of the fact
       that for any reason any other or others of them may be invalid or
       unenforceable in whole or in part.

              F. Section Headings. The section headings in this Escrow Agreement
       are for convenience only; they form no part of this Escrow Agreement and
       shall not affect its interpretation.

              G. Exhibits and Schedules. All Exhibits and Schedules attached
       hereto are hereby incorporated by reference into, and made a part of,
       this Escrow Agreement.

              H. No Third-Party Beneficiaries. This Escrow Agreement shall not
       confer any rights or remedies upon any person other than the parties and
       their respective heirs, personal representatives, successors and
       permitted assigns.

              I. Entire Agreement; Amendments. This Escrow Agreement (including
       the documents referred to herein) constitutes the entire agreement among
       the parties and supersedes any prior understandings, agreements, or
       representations by or among the parties, written or oral, that may have
       related in any way to the subject matter hereof. This Escrow Agreement
       may not be amended, supplemented or modified in whole or in part except
       by an instrument executed by all of the parties hereto.

              J. Construction. Any reference to any federal, state, local or
       foreign statute or law shall be deemed also to refer to the rules and
       regulations promulgated thereunder, unless the context requires
       otherwise. This Escrow Agreement shall be


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       neither construed against nor in favor of any of the parties hereto, but
       rather in accordance with the fair meaning of its content.

            K. Expenses. The parties hereto hereby agree that each party shall
       bear its own legal and accounting expenses incurred in the preparation of
       this Agreement and the consummation of the transactions hereunder.

       IN WITNESS WHEREOF, the parties have executed and delivered this Escrow
Agreement on the date first above written.


                              SUPERSHUTTLE INTERNATIONAL, INC.,
                              a Delaware corporation



                              By:   /s/ Thomas C. Lavoy
                                    -------------------------------------------
                                    Name: Thomas C. LaVoy
                                    Title: Secretary, CFO


                              SUPERSHUTTLE ACQUISITION CO. I INC.,
                              an Arizona corporation



                              By:   /s/ Thomas C. Lavoy
                                    -------------------------------------------
                                    Name: Thomas C. LaVoy
                                    Title: Secretary


                              PREFERRED TRANSPORTATION, INC.
                              a California corporation



                              By:   /s/ Steve Allan
                                    -------------------------------------------
                                    Name:  Steve Allan
                                    Title: President


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                              SHAREHOLDERS


                              /s/ Steve Allan
                              -------------------------------------------------
                                  Steve Allan


                              ORANGE COUNTY SHUTTLE ASSOCIATES, INC.

                              /s/ Dave Koscielak
                              -------------------------------------------------
                                  Dave Koscielak


                              ESCROW AGENT


                              By: /s/ Robert Splinter
                                  ----------------------------------------------
                                      Robert Splinter


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                                   SCHEDULE A


                          ALLOCATION OF PTI SHARES FOR
        DISTRIBUTION AMONG SHAREHOLDERS UPON EXERCISE OF REPURCHASE RIGHT



Steve Allan                                         49.2%

Dave Koscielak                                      49.2%

SuperShuttle                                         1.6%


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