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                                                                     EXHIBIT 2.1


                          AGREEMENT AND PLAN OF MERGER


         THIS AGREEMENT AND PLAN OF MERGER is made and entered into as of this
30th day of August, 2000, by and between Probex Corp., a Delaware corporation
(the "Surviving Corporation"), and Probex Corp., a Colorado corporation (the
"Merging Corporation"). The Merging Corporation and the Surviving Corporation
are sometimes collectively referred to herein as the "Constituent Corporations."

                                    RECITALS

         The Merging Corporation is a Colorado corporation having authorized
capital consisting of 50,000,000 shares of Common Stock, no par value per share,
of which 25,461,716 shares are issued and outstanding, and 10,000,000 of
Preferred Stock, no par value per share, of which 1,000,000 shares are
designated as Series A 10% Cumulative Convertible Preferred Stock, no par value
per share, of which 535,000 shares are issued and outstanding.

         The Surviving Corporation is a Delaware corporation having authorized
capital consisting of 100,000,000 shares of Common Stock, $0.001 par value per
share, of which 1,000 shares are issued and outstanding, all of which are owned
by the Merging Corporation, and 10,000,000 shares of Preferred Stock, par value
$0.001 per share, none of which are issued and outstanding, of which 550,000
shares are designated as Series A 10% Cumulative Convertible Preferred Stock,
$0.001 par value per share, none of which are issued and outstanding.

         The Merging Corporation and the Surviving Corporation have determined
it to be advisable for the Merging Corporation to merge with and into the
Surviving Corporation (the "Merger") pursuant to applicable provisions of the
Delaware General Corporate Law and the Colorado Business Corporation Act on the
terms hereinafter set forth, and the Boards of Directors of the Merging
Corporation and the Surviving Corporation have each approved and adopted this
Agreement and Plan of Merger and authorized the execution hereof.

                                 PLAN OF MERGER

         In consideration of the premises, the parties hereto do hereby adopt
and make this Agreement and Plan of Merger and prescribe the terms and
conditions of such Merger and the manner of carrying the same into effect, which
shall be as follows:

1.       Effective upon the later of (a) 10:00 A.M., Dallas, Texas time, on
         August 31, 2000, (b) the filing of the Certificate of Merger with the
         Office of the Delaware Secretary of State and (c) the filing of the
         Articles of Merger with the Office of the Colorado Secretary of State
         (such time and date, or filing as the case may be, being referred to
         herein as the "Effective Date"), the Merging Corporation shall be
         merged with and into the Surviving Corporation, and the separate
         existence of the Merging Corporation shall cease.

2.       The manner and basis of converting the issued and outstanding shares of
         the Merging Corporation's outstanding Common Stock , the outstanding
         stock options granted under the Merging Corporation's 1999 Omnibus
         Stock and Incentive Plan, as amended and restated (the "1999 Plan"),
         and the other outstanding options and warrants issued by the
         Corporation (collectively, the "Options and Warrants"), into shares of
         the Common


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         Stock, stock options and Options and Warrants of the Surviving
         Corporation shall be as follows:

    2.01      At the Effective Date, each of the shares of Common Stock of the
              Merging Corporation issued and outstanding or held as treasury
              shares on the Effective Date shall, without any action on the part
              of either of the Constituent Corporations or any holder of such
              stock, be changed and converted into an equal number of fully paid
              and nonassessable shares of the Common Stock of the Surviving
              Corporation.

    2.02      Each stock certificate which, prior to the Effective Date,
              represented issued shares of the Common Stock of the Merging
              Corporation shall be and become on the Effective Date, a
              certificate representing an identical number of shares of Common
              Stock of the Surviving Corporation, automatically by virtue of the
              Merger and without any action on the part of the holder hereof.

    2.03      Each stock option granted by the Merging Corporation (under or
              subject to the 1999 Plan of the Merging Corporation) and each
              Option and Warrant issued by the Merging Corporation and
              outstanding immediately prior to the Effective Date shall, by
              virtue of the Merger and without any action on the part of the
              holder thereof, be converted into and become a stock option,
              Option or Warrant, to purchase, upon the same terms and
              conditions, the number of shares of the Surviving Corporation's
              Common Stock (subject to further adjustment as may be provided in
              the 1999 Plan, or the applicable Options or Warrants) which is
              equal to the number of shares of the Merging Corporation's Common
              Stock which the holder thereof would have received had such holder
              exercised the option in full immediately prior to the Effective
              Date (whether or not such option was then exercisable). The price
              per share payable upon exercise under each of said options shall
              (subject to future adjustments as may be provided in the 1999
              Plan, or the applicable Options or Warrants) be equal to the
              exercise price per share thereunder immediately prior to the
              Effective Date. A number of shares of the Surviving Corporation's
              Common Stock shall be reserved for issuance upon the exercise of
              options equal to the number of shares of the Merging Corporation's
              Common Stock so reserved immediately prior to the Effective Date.

    2.04      The 1999 Plan and all outstanding stock options, thereunder, and
              each outstanding Option and Warrant, shall immediately prior to
              the Effective Date of the Merger be amended to the extent
              necessary to permit continuance of the 1999 Plan, and continuance
              of said stock options, and such Options and Warrants, into those
              of the Surviving Corporation following the Merger, notwithstanding
              any provisions heretofore contained in such 1999 Plan, or such
              Options and Warrants.

3.       The manner and basis of converting the issued and outstanding shares of
         the Merging Corporation's outstanding Preferred Stock into shares of
         Preferred Stock of the Surviving Corporation shall be as follows:

    3.01      At the Effective Date, each of the shares of Preferred Stock of
              the Merging Corporation issued and outstanding or held as treasury
              shares on the Effective Date shall, without any action on the part
              of either of the Constituent Corporations or any holder of such
              stock, be changed and converted into an equal number of fully paid
              and nonassessable shares of the Preferred Stock of the Surviving
              Corporation.

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    3.02      Each stock certificate which, prior to the Effective Date,
              represented issued shares of Preferred Stock of the Merging
              Corporation shall be and become on the Effective Date, a
              certificate representing an identical number of shares of
              Preferred Stock of the Surviving Corporation, automatically by
              virtue of the Merger and without any action on the part of the
              holder thereof.

4.       On the Effective Date, all of the shares of stock of the Surviving
         Corporation issued and outstanding on the Effective Date of the Merger
         shall be canceled and returned to the status of authorized but unissued
         shares.

5.       On the Effective Date, each employee benefit plan and incentive
         compensation plan to which the Merging Corporation is then a party
         shall be assumed by, and continue to be the plan of, the Surviving
         Corporation. To the extent any employee benefit plan or incentive
         compensation plan of the Merging Corporation or any of its subsidiaries
         provides for the issuance or purchase of, or otherwise relates to, the
         Merging Corporation's Common Stock, after the Effective Date such plan
         shall be deemed to provide for the issuance or purchase of, or
         otherwise relate to, the Surviving Corporation's Common Stock upon the
         same terms and conditions.

6.       The Officers and Directors of the Surviving Corporation on the
         Effective Date shall be and continue to be the Officers and Directors
         of the Surviving Corporation thereafter, until their successors are
         duly appointed or elected.

7.       The Articles of Incorporation and Bylaws of the Surviving Corporation,
         as they exist immediately prior to the Effective Date, shall remain in
         effect as the Articles of Incorporation and Bylaws of the Surviving
         Corporation thereafter, unaffected by the Merger, except any amendments
         authorized by the Merger.

8.       On the Effective Date, the Merging Corporation shall be merged with and
         into the Surviving Corporation, which shall continue its corporate
         existence under the laws of the State of Delaware. The separate
         existence and corporate organization of the Merging Corporation shall
         cease upon the Effective Date, and the Surviving Corporation shall
         possess all of the rights, privileges, immunities and franchises, as
         well as those of a public or of a private nature, of each of the
         Constituent Corporations; and all property, real, personal and mixed,
         and all debts due on whatever account, including subscriptions to
         shares, and all other choses in action, and all and every other
         interest, of or belonging to or due to each of the Constituent
         Corporations, shall be taken and deemed to be transferred to and vested
         in the Surviving Corporation without further act or deed; and the title
         to any real estate or any interest therein, vested in either of the
         Constituent Corporations shall not revert or be in any way impaired by
         reason of such Merger. The Surviving Corporation shall thenceforth be
         responsible and liable for all the liabilities and obligations of each
         of the Constituent Corporations, and any claims existing or action or
         proceeding pending by or against a Constituent Corporation may be
         prosecuted to judgment as if such Merger had not taken place. Neither
         the rights of creditors nor any liens upon the property of either
         Constituent Corporation shall be impaired by the Merger.

9.       This Agreement and Plan of Merger shall be submitted to the
         stockholders of each of the Constituent Corporations hereto in
         accordance with the applicable provisions of law, and the consummation
         of the Merger herein provided for is conditioned upon the approval and
         adoption hereof by the stockholders of the respective parties as
         provided by law.

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10.      This Agreement and Plan of Merger and the Merger herein contemplated
         may be abandoned by the Board of Directors of either of the Constituent
         Corporations at any time prior to the Effective Date. This Agreement
         may be amended, modified or supplemented at any time (before or after
         stockholder approval) prior to the Effective Date with the mutual
         consent of the Board of Directors of the Merging Corporation and the
         Surviving Corporation; provided, however, that this Agreement may not
         be amended, modified or supplemented after it has been approved by the
         Merging Corporation's stockholders in any manner which, in the judgment
         of the Board of Directors of the Merging Corporation, would have a
         material adverse effect on the rights of the Merging Corporation's
         stockholders or in any manner not permitted under applicable law.

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         IN WITNESS WHEREOF, the parties have caused this Agreement and Plan of
Merger to be executed by their duly authorized officers, all as of the day and
year first above written.



PROBEX CORP.,                            PROBEX CORP.,
a Colorado Corporation                   a Delaware Corporation


By:      /s/ BRUCE A. HALL               By:      /s/ BRUCE A. HALL
   ----------------------------------       ----------------------------------
         Bruce A. Hall,                           Bruce A. Hall,
         Chief Financial Officer                  Chief Financial Officer
         and Secretary                            and Secretary


Attest:  /s/ JOHN N. BROBJORG            Attest:  /s/ JOHN N. BROBJORG
       ------------------------------           ------------------------------
         John N. Brobjorg, Controller             John N. Brobjorg, Controller