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                                                                   Exhibit 10.33

                                                                  4 YEAR VESTING
                       HIGHWAYMASTER COMMUNICATIONS, INC.

                             STOCK OPTION AGREEMENT

         This OPTION AGREEMENT is entered into by and between HighwayMaster
Communications, Inc., a Delaware corporation (the "Company"), and the
undersigned employee of the Company's subsidiary, HighwayMaster Corporation,
(the "Optionee").


         1.    Grant of Option. The Company hereby grants to the Optionee 
effective as of the date set forth in Section 18 hereof (the "Date of Grant"),
the right and option (the "Option") to purchase up to the aggregate number of
shares of common stock, par value $.01 per share, of the Company (the "Common
Stock") set forth in Section 18 hereof, subject to adjustment pursuant to
Section 3 hereof and subject to the Optionee's acceptance and agreement to all
of the terms and conditions and restrictions described in the HighwayMaster
Communications, Inc. (formerly known as HM Holding Corporation) 1994 Stock
Option Plan, as amended (the "Plan"), a copy of which has been provided to the
Optionee, and to the further terms, conditions and restrictions set forth below.

         2.    Exercise Price. Subject to adjustment pursuant to Section 3, the
exercise price payable by the Optionee upon exercise of this Option is set forth
in Section 18 hereof.

         3.    Adjustments to Number of Shares and Option Price. The number of
shares of Common Stock exercisable under this Option and exercise price have
been adjusted to give effect to the purchase under that certain Subscription
Agreement dated February 4, 1994, by and among the Company and the Purchasers
listed therein by such Purchasers of an aggregate of 2,130.435 shares of Common
Stock of the Company. The number of shares and exercise price shall also be
adjusted as provided in Section 9.3 of the Plan.



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         4.    Tax Status. This Option will be treated as an "incentive stock
option" within the meaning of Section 422 of the Code to the extent that any
portion of this Option meets the requirements of Section 422 of the Code. To the
extent that any portion of this Option does not meet such Code requirements,
this Option shall be deemed a nonqualified stock option.

         5.    Exercise of Option. Subject to the terms of the Plan and this 
Option Agreement, as of the Date of Grant and each of the first, second, third
and fourth anniversaries of the Date of Grant, Optionee may exercise
(cumulatively) rights to acquire one-fifth of the Common Stock subject to the
Option. Notwithstanding the vesting schedule in the previous sentence, the
rights to purchase the Common Stock subject to the Opton OPTION will accelerate
and will vest the day immediately prior to the sale of more than 50% of the
common stock or assets of the Company, other than reorganizations performed
merely for administrative purposes.

         6.    Expiration of Option. This Option shall expire and cease to be
exercisable on the sixth anniversary of the Date of Grant or such earlier date
as may be specified in the Plan.

         7.    Termination of Affiliation.

               (a)    Subject to the following provisions of this Section 7 and 
         Article VI of the Plan, this Option may not be exercised unless at the
         time of exercise the Optionee is an Employee of the Company or a
         Subsidiary.

               (b)    If the Optionee's position as an Employee of the Company 
         or a Subsidiary shall terminate for any reason other than death, the
         Optionee may exercise this Option, to the same extent it was
         exercisable on the date of such termination, during the 60-day period
         following the date of such termination. In no event may the Optionee
         exercise this Option later than the date on which the Option would have
         expired under Section 6 hereof.



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               (c)    If the Optionee's position as an Employee of the Company 
         or a Subsidiary shall terminate by reason of the Optionee's death, the
         executor or administrator of the Optionee's estate or the person to
         whom this Option is transferred by will or the laws of descent or
         distribution may exercise this Option with respect to any or all shares
         covered by this Option within 60 days after the date of the Optionee's
         death.

         8.    Procedure to Exercise. This Option may be exercised only by 
delivery of a written notice to the Company at its principal office, stating the
number of shares of Common Stock as to which the Option is being exercised and
accompanied by payment in full in cash or by certified check of the exercise
price for all such shares.

         9.    Nontransferability of Option. This Option shall not be assignable
or transferable other than by will or the laws of descent and distribution and
shall be exercisable only by the Optionee during his lifetime.

         10.   Continued Employment or Retention. Subject to the terms of any
employment agreement between the Company and the Optionee, nothing herein shall
confer upon the Optionee any right to be continued in the employ or retention of
the Company or a Subsidiary or shall prevent the Company or Subsidiary which
employs or retains the Optionee from terminating such employment at any time,
with or without cause.

         11.   Rights as Shareholder. Nothing herein is intended to or shall 
give to the Optionee any right or status of any kind as a stockholder of the
Company in respect of any shares of Common Stock covered by this Option or
entitle the Optionee to any dividends or distributions thereon unless and until
such shares shall have been delivered to the Optionee and registered in the
Optionee's name.

         12.   Interpretation. If and when questions arise from time to time as 
to the intent, meaning or application of the provisions hereof or of the Plan,
such questions shall be decided by the Board 



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of Directors or the Committee in its sole discretion, and any such decision
shall be conclusive and binding on the Optionee. The Optionee hereby agrees that
this Option is granted and accepted subject to such condition and understanding.

         13.   Investment Representation. At such time or times as the Optionee
may exercise this Option, the Optionee shall, upon the request of the Company,
represent in writing (i) that the shares being acquired by the Optionee will not
be sold except pursuant to an effective registration statement, or applicable
exemption from registration, under the Securities Act of 1933, as amended, (ii)
that it is the Optionee's intention to acquire the shares being acquired for
investment only and not with a view to distribution thereof, and (iii) other
customary representations as the Company deems necessary or advisable. No shares
will be issued unless and until the Company is satisfied as to the accuracy of
such representations.

         14.   Withholding of Taxes. Upon exercise of this Option (either wholly
or in part), the Optionee must pay to the Company, or make arrangements
satisfactory to the Company regarding payment of, any federal, state or local
taxes of any kind required to be withheld in connection with the issuance to the
Optionee of Common Stock upon exercise of this Option.

         15.   Notices. All notices and other communications hereunder shall be 
in writing and shall be deemed to have been duly given if delivered personally,
mailed certified mail (return receipt requested) or sent by overnight delivery
service, cable, telegram, facsimile transmission or telex to the Optionee at the
address on the signature page hereof and to the Company at the address set forth
below or at such other addresses as shall be specified by the parties by like
notice:

                            HighwayMaster Communications, Inc.
                            1155 Kas Drive
                            Richardson, Texas  75081
                            Fax:  (972) 301-2263
                            Attn:  Secretary & General Counsel




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         16.   Defined Terms. All capitalized terms used herein and not 
otherwise defined shall have the meanings given them in the Plan.

         17.   Confidentiality. Unless otherwise permitted by the Chairman of 
the Board or the President of the Company, Optionee agrees to keep confidential
the terms of this Option Agreement (and the terms of any other Option Agreement
with any other employee of the Company known to Optionee) and shall not disclose
such terms to any other employee or otherwise.

         18.   Specified Information. This Option Agreement shall apply with
respect to the following specific information: 

               a.   Date of Grant: NOVEMBER 24, 1998

               b.   Name of Optionee: MICHAEL SMITH

               c.   Adjusted Number of Shares Covered by Option: 125,000

               d.   Option Exercise Price Per Share: $1.56

IN WITNESS WHEREOF, the undersigned have executed this Option Agreement to be
effective as of the Date of Grant set forth above.

                                      HIGHWAYMASTER COMMUNICATIONS, INC.

                                      By: /s/ JANA AHLFINGER BELL
                                         -----------------------------------
                                      Name:   Jana Ahlfinger Bell        
                                           ---------------------------------
                                      Title: President & CEO
                                            --------------------------------

                                        /s/ MICHAEL SMITH        11/30/98 
                                      --------------------------------------
                                      MICHAEL SMITH, Optionee


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