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                                                                   Exhibit 10.5


                                    RELEASE

         For good and valuable consideration, the receipt and adequacy of which
are hereby acknowledged and confessed, Highwaymaster Communications, Inc.,
formerly known as HM Holding Corporation, a Delaware corporation, and
HighwayMaster Corporation, a Delaware corporation (each, a "Releasor"), each on
behalf of itself, each of its predecessors, and each of its subsidiaries and
their respective predecessors (each of the foregoing being called a
"HighwayMaster Company") and the respective representatives, successors, and
assigns of each HighwayMaster Company (collectively, the "Releasing Parties"),
hereby fully releases, acquits, and forever discharges William C. Saunders
("Saunders") and his heirs, successors, assigns, and representatives (all of
such persons being called collectively, the "Released Parties"), of and from
any and all actions, causes of action, suits, debts, disputes, damages, claims,
obligations, liabilities, and demands of any kind whatsoever, at law or in
equity, whether matured, or unmatured, liquidated or unliquidated, vested or
contingent, choate or inchoate, known or unknown (collectively, "Claims") that
the Releasing Parties (or any of them) had, now has, or hereafter can, shall,
or may have against the Released Parties or any of them for, upon, or by reason
of any matter, cause, or thing whatsoever arising in connection with or related
to Saunders being, on or before the date of this Release, an officer, director,
employee, or agent of, or having any other relationship (contractual or
otherwise) with, a HighwayMaster Company, including but in no way limited to
matters that involve any alleged negligence, misconduct, breach of contract,
breach of fiduciary or other duty, malfeasance, misfeasance, criminal conduct,
or violation of law by Saunders.

          EACH RELEASING PARTY HEREBY ACKNOWLEDGES AND AGREES THAT THIS
RELEASE RELEASES CLAIMS ARISING FROM THE ACTUAL OR ALLEGED NEGLIGENCE
OR OTHER FAULT OF THE RELEASED PARTIES.

         Each Releasor hereby agrees that it will not assert, and that it is
estopped from asserting, against the Released Parties, or any of them, any
Claim that it has released in this Release.

         This Release will be null and void and of no force or effect as to any
Released Party with respect to any Releasing Party if that certain Release
dated the date hereof executed by Saunders for the benefit of any Releasing
Party is found, in a final, nonappealable order of a court of competent
jurisdiction entered after pursuit and exhaustion of all appeals, to be
ineffective with respect to such Releasing Party in some material respect and
such Released Party or its successor in interest asserts a Claim against such
Releasing Party that would have been released but for such order.

         No waiver or amendment of this Release, or the promises, obligations,
or conditions herein, shall be valid unless set forth in writing and signed by
the party against whom such waiver or amendment is to be enforced, and no
evidence of any waiver or amendment of this Release shall be ordered or
received in evidence in any proceeding, arbitration or litigation between the
Releasing Parties (or any of them) and the Released Parties (or any of them)
arising out of or affecting this Release unless such waiver or amendment is in
writing and signed as stated above.




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         Each Releasor hereby represents and warrants that it has not assigned,
pledged, or transferred in any manner to any person or entity any Claim that is
the subject of this Release. The Releasors, jointly and severally, shall
indemnify the Released Parties and each of them from and against all Claims
that are the subject of this Release that are asserted by any person or entity
by or through any Releasing Party or as a result of any assignment, pledge, or
transfer that caused the foregoing representation to be false.

         Notwithstanding the foregoing, nothing in this Release is intended to
release any prospective Claims arising on or after the date hereof under or
pursuant to (a) the provisions of that certain Employment Agreement dated as of
February 4, 1994, executed by HighwayMaster Corporation and Saunders, as
amended through September 1, 1998 (except to the extent such amendment of the
Employment Agreement releases, by its own terms, certain claims and provisions
contained in the Employment Agreement prior to its amendment) that are
applicable after or arise as a result of termination of employment; (b) that
certain Stock Option Agreement executed by HighwayMaster Communications, Inc.
and Saunders dated as of June 13, 1994, as amended on September 18, 1998,
effective as of June 13, 1994; or (c) that certain Stock Option Agreement
executed by HighwayMaster Communications, Inc. and Saunders dated as of
September 18, 1998.

         The provisions of this Release shall be specifically enforceable.

         Executed in one or more counterparts as of December 15 , 1998.


                                        HIGHWAYMASTER COMMUNICATIONS, INC.


                                        By: /S/ Jana A. Bell                  
                                            ----------------------------------
                                            Jana A. Bell, President and CEO


                                        HIGHWAYMASTER CORPORATION


                                        By: /S/ Jana A. Bell                 
                                            Jana A. Bell, President and CEO



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