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                                                                     EXHIBIT 3.1

                          CERTIFICATE OF INCORPORATION
                                       OF
                          VISTA ENERGY RESOURCES, INC.


         FIRST:  The name of the corporation (the "Corporation") is Vista
Energy Resources, Inc.

         SECOND: The registered office of the Corporation in the State of
Delaware is located at Corporation Trust Center, 1209 Orange Street, in the
City of Wilmington, County of New Castle.  The name of the registered agent of
the Corporation at the address is The Corporation Trust Company.

         THIRD:  The purpose for which the Corporation is organized is to
engage in any and all lawful acts and activities for which corporations may be
organized under the General Corporation Law of the State of Delaware (the
"DGCL") and the Corporation shall have the power to perform all lawful acts and
activities.

         FOURTH: The Corporation will have perpetual existence.

         FIFTH:  The total number of shares of stock that the Corporation shall
have authority to issue is 60,000,000 shares of capital stock classified as (i)
50,000,000 shares of common stock, par value $.01 per share ("Common Stock")
and (ii) 10,000,000 shares of preferred stock, par value $.01 per share
("Preferred Stock").

         The designations and the powers, preferences, rights, qualifications,
limitations, and restrictions of the Preferred Stock and Common Stock are as
follows:

         1.      Provisions Relating to the Preferred Stock.

                 (a)      The Preferred Stock may be issued form time to time
         in one or more series, the shares of each series to have any
         designations and powers, preferences, rights, qualifications,
         limitations and restrictions thereof, as are stated and expressed in
         this Article Fifth and in the resolution or resolutions providing for
         the issue of such series adopted by the board of directors of the
         Corporation as hereafter prescribed (a "Preferred Stock Designation").

                 (b)      Authority is hereby expressly granted to and vested
         in the board of directors of the Corporation to authorize the issuance
         of the Preferred Stock from time to time in one or more series, and
         with respect to each series of the Preferred Stock, to fix and state
         by the
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         resolution or resolutions from time to time adopted providing for the
         issuance thereof the following:

                          (i)     whether or not the series is to have voting
                 rights, full, special or limited, or is to be without voting
                 rights, and whether or not such series is to be entitled to
                 vote as a separate class either alone or together with the
                 holders of one or more other classes or series of stock;

                          (ii)    the number of shares to constitute the series
                 and the designations thereof;

                          (iii)   the preferences and relative, participating,
                 optional, or other special rights, if any, and the
                 qualifications, limitations or restrictions thereof, if any,
                 with respect to any series;

                          (iv)    whether or not the shares of any series shall
                 be redeemable at the option of the Corporation or the holders
                 thereof or upon the happening of any specified event, and, if
                 redeemable, the redemption price or prices (which may be
                 payable in the form of cash, notes, securities or other
                 property), and the time or times at which and the terms and
                 conditions upon which such shares shall be redeemable and the
                 manner of redemption;

                          (v)     whether or not the shares of a series shall
                 be subject to the operation of retirement or sinking funds to
                 be applied to the purchase or redemption of such shares for
                 retirement, and, if such retirement or sinking fund or funds
                 are to be established, the periodic amount thereof, and the
                 terms and provisions relative to the operation thereof;

                          (vi)    the dividend rate, whether dividends are
                 payable in cash, stock of the Corporation or other property,
                 the conditions upon which and the times when such dividends
                 are payable, the preference to or the relation to the payment
                 of the dividends payable on any other class or classes or
                 series of stock, whether or not such dividends shall be
                 cumulative or noncumulative, and if cumulative, the date or
                 dates from which such dividends shall accumulate;

                          (vii)   the preferences, if any, and the amounts
                 thereof which the holders of any series thereof shall be
                 entitled to receive upon the voluntary or involuntary
                 dissolution of, or upon any distribution of the assets of, the
                 Corporation;

                          (viii)  whether or not the shares of any series, at
                 the option of the Corporation or the holder thereof or upon
                 the happening of any specified event, shall be convertible
                 into or exchangeable for the shares of any other class or
                 classes of

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                 stock, securities or other property of the Corporation and the
                 conversion price or prices or ratio or ratios or the rate or
                 rates at which such conversion or exchange may be made, with
                 such adjustments, if any, as shall be stated and expressed or
                 provided for in such resolution or resolutions; and

                          (ix)    any other special rights and protective
                 provisions with respect to any series as the board of
                 directors of the Corporation may deem advisable.

                 (c)      The shares of each series of the Preferred Stock may
         vary from the shares of any other series thereof in any or all of the
         foregoing respects and in any other manner.  The  board of directors
         of the Corporation may increase the number of shares of the Preferred
         Stock designated for any existing series by a resolution adding to
         such series authorized and unissued shares of the Preferred Stock not
         designated for any other series.  Unless otherwise provided in the
         Preferred Stock Designation, the board of directors of the Corporation
         may decrease the number of shares of the Preferred Stock designated
         for any existing series by a resolution subtracting from such series
         authorized and unissued shares of the Preferred Stock designated for
         such existing series, and the shares so subtracted shall become
         authorized, unissued and undesignated shares of the Preferred Stock.

         2.      Provisions Relating to the Common Stock.

                 (a)      The holders of shares of the Common Stock shall be
         entitled to vote upon all matters submitted to a vote of the common
         stockholders of the Corporation and shall be entitled to one vote for
         each share of the Common Stock held.

                 (b)      Subject to the prior rights and preferences, if any,
         applicable to shares of the Preferred Stock or any class or series
         thereof, and subject to the right of participation, if any, of the
         holders of the Preferred Stock in any dividends, the holders of shares
         of the Common Stock shall be entitled to receive such dividends
         (payable in cash, stock or otherwise) as may be declared thereon by
         the board of directors of the Corporation at any time and from time to
         time out of any funds of the Corporation legally available therefor.

                 (c)      In the event of any voluntary or involuntary
         liquidation, dissolution or winding-up of the Corporation, after
         distribution in full of the preferential amounts, if any, to be
         distributed to the holders of shares of the Preferred Stock or any
         class or series thereof, and subject to the right of participation, if
         any, of the holders of the Preferred Stock in any dividends, the
         holders of shares of the Common Stock shall be entitled to receive all
         of the remaining assets of the Corporation available for distribution
         to its stockholders, ratably in proportion to the  number of shares of
         the Common Stock held by them.  A liquidation, dissolution, or
         winding-up of the Corporation, as such terms are used in this
         Paragraph (c), shall not be deemed to be occasioned by or to include
         any consolidation or merger of the





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         Corporation with or into any other corporation or corporations or
         other entity or a sale, lease, exchange or conveyance of all or a part
         of the assets of the Corporation.

         3.      General.

                 (a)      Subject to the foregoing provisions of this
         Certificate of Incorporation, the Corporation may issue shares of its
         Preferred Stock and Common Stock from time to time for such
         consideration (not less than the par value thereof) as may be fixed by
         the board of directors of the Corporation, which is expressly
         authorized to fix the same in its absolute discretion subject to the
         foregoing conditions.  Shares so issued for which the consideration
         shall have been paid or delivered to the Corporation shall be deemed
         fully paid stock and shall not be liable to any further call or
         assessment thereon, and the holders of such shares shall not be liable
         for any further payments in respect of such shares.

                 (b)      The Corporation shall have authority to create and
         issue rights and options entitling their holders to purchase shares of
         the Corporation's capital stock of any class or series or other
         securities of the Corporation, and such rights and options shall be
         evidenced by instrument(s) approved by the board of directors of the
         Corporation.  The board of directors of the Corporation shall be
         empowered to set the exercise price, duration, times for exercise and
         other terms of such rights or options; provided, however, that the
         consideration to be received for any share of capital stock subject
         thereto shall not be less than the par value thereof.

                 (c)      No stockholder of the Corporation shall by reason of
         his or her holding shares of any class of capital stock of the
         Corporation have any preemptive or preferential right to acquire or
         subscribe for any additional, unissued or treasury shares (whether now
         or hereafter acquired) of any class of capital stock of the
         Corporation now or hereafter to be authorized, or any notes,
         debentures, bonds or other securities convertible into or carrying any
         right, option or warrant to subscribe for or acquire shares of any
         class of capital stock of the Corporation now or hereafter to be
         authorized, whether or not the issuance of any such shares or such
         notes, debentures, bonds or other securities would adversely affect
         the dividends or voting or other rights of that stockholder.

                 (d)      Cumulative voting of shares of any capital stock
         having voting rights is prohibited.

         SIXTH:  The number and terms of the board of directors of the
Corporation and the procedures to elect directors, to remove directors, and to
fill vacancies in the board of directors shall be as follows:

                 1.       The number of directors that shall constitute the
         whole board of directors shall from time to time be fixed exclusively
         by the board of directors by a resolution adopted by





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         a majority of the members of the board of directors serving at the
         time of that vote.  In no event shall the number of directors that
         constitutes the whole board of directors be fewer than two or more
         than twenty-one.  The number of directors constituting the initial
         board of directors is two, and the name of each person who is to serve
         as director until the first annual meeting of stockholders or until
         his successor is elected and qualified is C. Randall Hill and Kenneth
         A. Hersh. The mailing address of each of such persons is 550 West
         Texas Avenue, Suite 700, Midland, Texas 79701.  No decrease in the
         number of directors shall have the effect of shortening the term of
         any incumbent director.  Directors of the Corporation need not be
         elected by written ballot unless the bylaws of the Corporation
         otherwise provide.

                 2.       Vacancies in the board of directors resulting from
         death, resignation, retirement, disqualification, removal from office
         or other cause and newly-created directorships resulting from any
         increase in the authorized number of directors shall be filled by a
         majority vote of the remaining directors then in office, though less
         than a quorum, or by the sole remaining director, and each director so
         chosen shall hold office until the first meeting of stockholders held
         after his election for the purpose of electing directors and until his
         or her successor is elected and qualified or until his or her earlier
         death, resignation or removal from office.

                 3.       No director of the Corporation shall be removed
         before the expiration of that director's term of office except for
         cause and by an affirmative vote of a majority of the shares entitled
         to vote thereon cast at the annual meeting of stockholders or at any
         special meeting of stockholders called for this purpose by a majority
         of the members of the board of directors serving at the time of that
         vote.

                 4.       Notwithstanding the foregoing, the election, removal
         and the filling of vacancies with respect to directors elected
         separately by any series of Preferred Stock shall be governed by the
         terms of the Preferred Stock Designation establishing such series.

         SEVENTH:         All of the power of the Corporation, insofar as it
may be lawfully vested by this Certificate of Incorporation in the board of
directors, is hereby conferred upon the board of directors of the Corporation.
In furtherance of and not in limitation of that power or the powers conferred
by law, (1) a majority of the whole board of directors shall have the power to
adopt, amend, and repeal the bylaws of the Corporation; (2) the board of
directors may designate and appoint from among its members one or more
committees, and may designate one or more of its members as alternate members,
who may, subject to any limitations imposed by the board of directors, replace
absent or disqualified members at any meeting of such committee; (3) the
stockholders of the Corporation shall have no power to appoint or remove
directors as members of committees of the board of directors, nor to abrogate
the power of the board of directors to establish any such committees or the
power of any such committee to exercise the powers and authority of the board
of directors; (4) the stockholders of the Corporation shall have no power to
elect or remove officers of the Corporation nor to abrogate the power of the
board of directors to elect and remove





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officers of the Corporation; and (5) notwithstanding any other provision of
this Certificate of Incorporation or any provision of law that might otherwise
permit a lesser or no vote, but in addition to any affirmative vote of the
holders of any particular class or series of the capital stock of the
Corporation required by law or by this Certificate of Incorporation, the bylaws
of the Corporation shall not be adopted, altered, amended or repealed by the
stockholders of the Corporation except in accordance with the provisions of the
bylaws and by the vote of the holders of not less than a majority in voting
power of the outstanding shares of stock then entitled to vote upon the
election of directors, voting together as a single class or such higher vote as
is set forth in the bylaws.  The bylaws of the Corporation shall not contain
any provision inconsistent with this Certificate of Incorporation.

         EIGHTH: Except as otherwise required by law, special meetings of the
common stockholders of the Corporation, and any proposals to be considered at
such meetings, may only be called by the Board of Directors and no common
stockholder may require the Board of Directors to call a special meeting of the
common stockholders or propose business at such a meeting.

         NINTH:  No contract or transaction between the Corporation and one or
more of its directors, officers or stockholders or between the Corporation and
any other person (as used herein "person" means a corporation, partnership,
association, firm, trust, joint venture, political subdivision or
instrumentality) or other organization in which one or more of its directors,
officers or stockholders are directors, officers or stockholders, or have a
financial interest, shall be void or voidable solely for this reason, or solely
because the director or officer is present at or participates in the meeting of
the board of directors or committee which authorizes the contract or
transaction, or solely because his, her or their votes are counted for such
purpose, if:  (1) the material facts as to his or her relationship or interest
and as to the contract or transaction are disclosed or are known to the board
of directors or the committee, and the board of directors or committee in good
faith authorizes the contract or transaction by the affirmative votes of a
majority of the disinterested directors, even though the disinterested
directors be less than a quorum; or (2) the material facts as to his or her
relationship or interest and as to the contract or transaction are disclosed or
are known to the stockholders entitled to vote thereon, and the contract or
transaction is specifically approved in good faith by a vote of the
stockholders; or (3) the contract or transaction is fair as to the Corporation
as of the time it is authorized, approved or ratified by the board of
directors, a committee thereof, or the stockholders.  Interested directors may
be counted in determining the presence of a quorum at a meeting of the board of
directors or of a committee which authorizes the contract or transaction.

         TENTH:  The name of the incorporator is Kathryn Truett and her mailing
address is c/o Vinson & Elkins L.L.P., 3700 Trammell Crow Center, 2001 Ross
Avenue, Dallas, Texas  75201.

         ELEVENTH:        The Corporation shall indemnify any person who was,
is, or is threatened to be made a party to a proceeding (as hereinafter
defined) by reason of the fact that he or she (1) is or was a director or
officer of the Corporation or (2) while a director or officer of the





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Corporation, is or was serving at the request of the Corporation as a director,
officer, partner, venturer, proprietor, trustee, employee, agent or similar
functionary of another foreign or domestic Corporation, limited liability
company, association, partnership, joint venture, sole proprietorship, trust,
employee benefit plan or other enterprise, entity or organization, to the
fullest extent permitted under the DGCL, as the same exists or may hereafter be
amended.  Such right shall be a contract right as such shall run to the benefit
of any director or officer who is elected and accepts the position of director
or officer of the Corporation or elects to continue to serve as a director or
officer of the Corporation while this Article Eleventh is in effect.  Any
repeal or amendment of this Article Eleventh shall be prospective only and
shall not limit the rights of any such director or officer or the obligations
of the Corporation with respect to any claim arising from or related to the
services of such director or officer in any of the foregoing capacities prior
to any such repeal or amendment to this Article Eleventh.  Such right shall
include the right to be paid by the Corporation expenses (including attorneys'
fees) incurred in defending any such proceeding in advance of its final
disposition to the maximum extent permitted under the DGCL, as the same exists
or may hereafter be amended.  If a claim for indemnification or advancement of
expenses hereunder is not paid in full by the Corporation within sixty days
after a written claim has been received by the Corporation, the claimant may at
any time thereafter bring suit against the Corporation to recover the unpaid
amount of the claim, and, if successful in whole or in part, the claimant shall
also be entitled to be paid the expenses of prosecuting such claim.  It shall
be a defense to any such action that such indemnification is not permitted
under the DGCL, but the burden of proving such defense shall be on the
Corporation.  Neither the failure of the Corporation (including its board of
directors or any committee thereof, independent legal counsel or stockholders)
to have made its determination prior to the commencement of such action that
indemnification of the claimant is permissible in the circumstances nor an
actual determination by the Corporation (including its board of directors or
any committee thereof, independent legal counsel or stockholders) that such
indemnification is not permissible shall be a defense to the action or create a
presumption that such indemnification is not permissible.  In the event of the
death of any person having a right of indemnification under the forgoing
provisions, such right shall inure to the benefit of his or her heirs,
executors, administrators, and personal representatives.  The rights conferred
above shall not be exclusive of any other right which any person may have or
hereafter acquire under any statute, bylaw, resolution of stockholders or
directors, agreement or otherwise.

         The Corporation may additionally indemnify any employee or agent of
the Corporation to the fullest extent permitted by law.

         As used herein, the term "proceeding" means any threatened, pending or
completed action, suit or proceeding, whether civil, criminal, administrative,
arbitrative or investigative, any appeal in such an action, suit or proceeding,
and any inquiry or investigation that could lead to such an action, suit or
proceeding.

         TWELFTH:         A director of the Corporation shall not be personally
liable to the Corporation or its stockholders for monetary damages for breach
of fiduciary duty as a director, except for





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liability (1) for any breach of the director's duty of loyalty to the
Corporation or its stockholders, (2) for acts or omissions not in good faith or
which involve intentional misconduct or knowing violation of law, (3) under
Section 174 of the DGCL, as the same exists or as such provision may hereafter
be amended, supplemented or replaced, or (4) for any transaction from which the
director derived an improper personal benefit.  Any repeal or amendment of this
Article Twelfth by the stockholders of the Corporation shall be prospective
only, and shall not adversely affect any limitation on the personal liability
of a director of the Corporation arising from an act or omission occurring
prior to the time of such repeal or amendment.  In addition to the
circumstances in which a director of the Corporation is not personally liable
as set forth in the foregoing provisions of this Article Twelfth, a director
shall not be liable to the Corporation or its stockholders to such further
extent as permitted by any law hereafter enacted, including without limitation
any subsequent amendment to the DGCL.  Notwithstanding any other provisions of
this Certificate of Incorporation or any provision of law that might otherwise
permit a lesser or no vote, but in addition to any affirmative vote of the
holders of any particular class or series of the capital stock of the
Corporation required by law or by this Certificate of Incorporation, the
affirmative vote of the holders of not less than two-thirds in voting power of
the shares of the Corporation then entitled to be voted in an election of
directors, voting together for a single class, shall be required to amend or
repeal or to adopt any provision inconsistent with this Article Twelfth.

         I, the undersigned, being the incorporator hereinbefore named, for the
purpose of forming a corporation pursuant to the Delaware General Corporation
Law, do make this certificate, hereby declaring that this is my act and deed
and that the facts herein stated are true, and accordingly have hereunto set my
hand this 22nd day of May, 1998.



                                               ---------------------------------
                                               Kathryn Truett





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