EXHIBIT 10.22

                       PIONEER NATURAL RESOURCES COMPANY
                               SEVERANCE AGREEMENT


     This Severance  Agreement  (this  "Agreement")  is entered into,  effective
August  8,  1997,   between  Pioneer  Natural  Resources   Company,  a  Delaware
corporation  ("Parent"),  and Larry N. Paulsen (the "Officer").  As used in this
Agreement,  the term "Company"  shall be deemed to include Parent and its direct
or indirect wholly-owned subsidiaries.

                                    Recitals

     A. Officer is currently serving as an officer of Parent. Parent and Officer
desire  to  enter  into an  agreement  governing  certain  matters  relating  to
Officer's employment with the Company,  including compensation  arrangements and
restrictions on Officer's use of Company information.

     B.  Parent  acknowledges  that  Officer is a  significant  employee  of the
Company,  possessing skills and knowledge instrumental to the successful conduct
of the  Company's  business.  Parent  is  willing  to  enter  into  a  severance
arrangement  with  Officer  in order to better  ensure  itself of the  continued
management  services of Officer for itself and its subsidiaries and, in part, to
induce  Officer to continue to provide  those  services  and subject  himself to
certain restrictions regarding the use of Company information.

     C.  Officer is willing to  subject  himself to the  restrictions  mentioned
above in part to induce  Parent to enter into a  compensation  arrangement  that
provides  for,  among other  things,  the payment of certain  benefits  upon the
termination of Officer's employment under certain circumstances.

     Now,  therefore,  for and in  consideration  of the  mutual  covenants  and
agreements set forth herein and for other good and valuable  consideration,  the
receipt and  sufficiency of which are hereby  acknowledged,  the parties to this
Agreement hereby agree as follows:

     1. Position and Duties. Officer shall serve Parent as Vice President,  and,
in so doing, shall report to Parent's Board of Directors (the "Board"), Parent's
Chief  Executive  Officer (the "Chief  Executive  Officer") or such  officers of
Parent as is prescribed by Parent's  bylaws,  by  resolutions of the Board or by
direction of the Chief  Executive  Officer.  Officer shall have  supervision and
control over, and responsibility for, such management and operational  functions
of the Company currently assigned to such position, and shall have such other or
different  powers and duties  (including  holding officer  positions with one or
more  subsidiaries  of Parent),  as may from time to time be  prescribed  by the
Board or the Chief  Executive  Officer,  so long as such  functions,  powers and
duties are reasonable  and customary for a Vice President  serving an enterprise
comparable to Parent.

     2.  Devotion of  Efforts.  So long as Officer is serving the Company in the
capacities  described  in  Section 1, he shall  devote his full time,  skill and
attention and his best efforts during normal  business hours to the business and
affairs of the  Company to the extent  necessary  to  discharge  faithfully  and
efficiently his duties and  responsibilities  described in Section 1, except for
usual,  ordinary and customary periods of vacation and absence due to illness or
other  disability  or such  periods of leave as are  approved  in writing by the
Board or the Chief Executive  Officer.  The provisions of this Section shall not
be construed to prevent Officer from making  investments in other  businesses or
enterprises,  so long as such investments do not violate the Company's  conflict
of interest  policies or require  the  provision  of services by Officer to such
businesses  or  enterprises  to an extent that would  interfere  in any material
respect with the  performance of Officer's  duties and  responsibilities  to the
Company.






     3.  Compensation.

         (a)  Base Salary. As compensation for Officer's services, the Company
shall pay Officer an annualized base salary of a specified amount per annum (the
"Base  Salary").  The  Base  Salary  shall be  payable  in  substantially  equal
semi-monthly  installments.   The  Compensation  Committee  of  the  Board  (the
"Compensation  Committee") may review the Base Salary periodically and may grant
such  increases,  or  effect  such  reductions,   in  the  Base  Salary  as  the
Compensation   Committee   considers   appropriate   in  accordance   with  such
compensation  guidelines and policies as it may establish from time to time. The
Base Salary applicable from time to time for any period of Officer's  employment
with the Company,  commencing on the effective date of this Agreement,  shall be
identified on Schedule A attached hereto, which shall be amended periodically to
reflect any increases or reductions effected by the Compensation Committee.

         (b) Bonuses. Officer shall be entitled to receive (in addition to the
Base Salary) such annual or other periodic bonus as the  Compensation  Committee
may award in accordance with such compensation guidelines and policies as it may
establish from time to time.

         (c) Other Benefits. Officer shall be entitled to participate in, or
receive  benefits under,  any employee  benefit plan or other  arrangement  made
available  now or in the  future by the  Company  to the  officers  of Parent (a
"Benefit Plan"), subject to the terms,  conditions and overall administration of
such Benefit Plan. Officer's participation in, or receipt of benefits under, any
Benefit Plan shall be in addition to (and not in lieu of) the Base Salary.

         (d) Vacations and Holidays. Officer shall be entitled to the number of
paid vacation days in each calendar year  determined by Parent from time to time
for its officers and shall be entitled to all paid holidays given by the Company
to its employees in general.

     4.  Relocation.  Officer  shall be  required  to  perform  his  duties  and
responsibilities hereunder at Parent's offices located in Midland, Texas. If the
Company  requires  Officer to perform  his  duties and  responsibilities  at any
location that is more than 50 miles from the nearest border of Midland, Texas (a
"New  Location") and,  within 30 days after  receiving  notice thereof,  Officer
accepts such relocation  rather than terminating his employment with the Company
pursuant to Section 5(a), the Company shall pay to Officer,  or shall  reimburse
Officer for (upon submission of reasonably detailed evidence thereof), such sums
as are  provided  for  under the  Relocation  Policy  for  Exempt  Employees  as
established by Parent.

     5.  Termination of Employment.

         (a)  Right to Terminate. Officer's employment with the Company
(including his officer position with Parent) shall be terminated upon the death,
Disability  (as  defined  in  subsection  (f)(3)  of  this  Section)  or  Normal
Retirement  (as defined in  subsection  (f)(6) of this  Section) of Officer.  In
addition,  Officer's employment with the Company (including his officer position
with Parent) may be  terminated  at any time and for any reason as a result of a
dismissal or other action by the Company or as a result of a voluntary action by
Officer.  Any  such  termination  of  employment  is  referred  to  herein  as a
"Termination of Employment."

         (b) Notice of Termination.

             (1) Any Termination of Employment that is the result of Officer's
         Disability shall be communicated by the Company to Officer in a written
         notice thereof. Such notice shall state that, in the opinion of the
         Board, Officer is suffering from a Disability and such Disability is
         the reason for the Termination of Employment.

             (2) Any Termination of Employment that is the result of Officer's
         Normal Retirement shall be communicated by Officer to Parent by a
         written notice thereof. Such notice shall state that Officer is
         retiring and shall specify the date of such Termination of Employment,
         which shall be not less than 30 days following the date such notice is
         received by Parent.






             (3) Any Termination of Employment that is the result of a dismissal
         or other action by the Company (but is not the result of Officer's
         Disability) shall be communicated by the Company to Officer by a
         written notice thereof. Such notice shall state whether or not (in the
         Company's opinion) the Termination of Employment constitutes a
         Termination for Cause (as defined in subsection (f)(7) of this Section)
         and, if so, shall set forth in reasonable detail facts and
         circumstances constituting a basis for such Termination for Cause.

             (4) Any Termination of Employment that is the result of a voluntary
         action by Officer (but is not the result of Officer's Normal
         Retirement) shall be communicated by Officer to Parent by written
         notice thereof. Such notice shall state whether or not (in Officer's
         opinion) the Termination of Employment constitutes a Termination for
         Good Reason (as defined in subsection (0(8) of this Section) and, if
         so, shall set forth in reasonable detail the facts and circumstances
         claimed as the basis for such Termination for Good Reason. Such notice
         shall also specify the date of such Termination of Employment, which
         (if the Termination of Employment does not constitute a Termination for
         Good Reason) shall be not less than 30 days following the date such
         notice is received by Parent.

         (c)  Date of Termination of Employment. For purposes of this Agreement,
the date of a  Termination  of  Employment  shall be (1) if the  Termination  of
Employment is the result of Officer's  death, the date of such death, (2) if the
Termination  of  Employment is the result of Officer's  Disability,  the date on
which the notice  described in subsection  (b)(1) of this Section is received by
Officer,  (3) if the Termination of Employment is the result of Officer's Normal
Retirement,  the date specified in the notice described in subsection  (b)(2) of
this Section,  (4) if the Termination of Employment is the result of a dismissal
or other action by the Company (but is not the result of Officer's  Disability),
the date on which the notice  described in subsection  (b)(3) of this Section is
received by the Officer,  and (5) if the Termination of Employment is the result
of a  voluntary  action by Officer  (but is not the result of  Officer's  Normal
Retirement),  the date specified in the notice described in subsection (b)(4) of
this Section.

         (d)  Payments Due Upon Termination of Employment. The provisions of
subsections (d)(1) and (d)(3) of this Section shall apply to any
Termination of Employment, whether occurring prior to, at the time of
or at any time following a Change in Control (as defined in subsection
(f)(2) of this Section); and the provisions of subsection (d)(2) of
this Section shall apply only to any Termination of Employment prior to
a Change in Control.

             (1) Death, Disability or Normal Retirement. If the
         Termination of Employment is the result of Officer's death, Disability
         or Normal Retirement, the Company shall pay the following amounts to
         Officer (or his estate or personal representative):

                       (A) The Base Salary (at the rate in effect on the date of
                  such Termination of Employment, as identified on Schedule A)
                  through and including the date of such Termination of
                  Employment, to the extent not already paid, which amount shall
                  be paid in cash on the first normal semi-monthly Base Salary
                  payment date immediately succeeding the date of such
                  Termination of Employment;

                       (B) Any amounts arising from Officer's participation in,
                  or benefits under, any Benefit Plan through and including the
                  date of such Termination of Employment, which amounts shall be
                  payable in accordance with the terms and conditions of such
                  Benefit Plan; and

                       (C) An amount equal to one full year's Base Salary (at
                  the rate in effect on the date of such Termination of
                  Employment, as identified on Schedule A), which amount shall
                  be paid in cash within 30 days following the date of such
                  Termination of Employment.





             (2)  Termination for Good Reason or Not for Cause. If the
         Termination of Employment (i) is the result of a dismissal or
         other action by the Company (but is not the result of
         Officer's Disability) and does not constitute a Termination
         for Cause or (ii) is the result of a voluntary action by
         Officer (but is not the result of Officer's Normal Retirement)
         and constitutes a Termination for Good Reason, the Company
         shall pay the following amounts, and provide the following
         benefits to Officer:

                       (A) The Base Salary (at the rate in effect on the date of
                  such Termination of Employment, as identified on Schedule A)
                  through and including the date of such Termination of
                  Employment, which amount shall be paid in cash on the date of
                  such Termination of Employment;

                       (B) Any amount arising from Officer's participation in,
                  or benefits under, any Benefit Plan through and including the
                  date of such Termination of Employment, which amounts shall be
                  payable in accordance with the terms and conditions of such
                  Benefit Plan;

                       (C) An amount equal to one full year's Base Salary (at
                  the rate in effect on the date of such Termination of
                  Employment, as identified on Schedule A), which amount shall
                  be paid in cash on the date of such Termination of Employment;

                       (D) For a period of one year following the date of such
                  Termination of Employment, a continuation of all health
                  insurance coverage applicable at the time of such Termination
                  of Employment to Officer and his immediate family under any
                  Benefit Plan; and

                       (E) With respect to a Termination of Employment described
                  in Section 5(d)(2)(i), an amount equal to one-twelfth (1/12)
                  of the Officer's Base Salary, which amount shall be paid in
                  cash on the date of such Termination of Employment.

             (3)  Termination for Cause or Not for Good Reason. If the
         Termination  of  Employment  (i) is the result of a dismissal or other
         action by the Company (but is not the result of Officer's  Disability)
         and  constitutes a Terminaation  for Cause or (ii) is the  result of a
         voluntary  action by Officer (but is not the result of Officer's Normal
         Retirement) and does not constitute a Termination  for Good Reason,
         the Company  shall pay the  following  amounts to Officer:

                       (A) The Base Salary (at the rate in effect on the date of
                  such Termination of Employment, as identified on Schedule A)
                  through and including the date of such Termination of
                  Employment, which amount shall be paid in cash on the first
                  normal semi-monthly Base Salary payment date immediately
                  succeeding the date of such Termination of Employment; and

                       (B) Any amounts arising from Officer's participation in,
                  or benefits under, any Benefit Plan through and including the
                  date of such Termination of Employment, which amounts shall be
                  payable in accordance with the terms and conditions of such
                  Benefit Plan.

             (4) Payment Contingent on Release. If Officer's
         Termination of Employment is prior to a Change in Control (and only in
         that event), and Officer is otherwise entitled to the payment provided
         in subsection (d)(2) of this Section, then such payment shall be
         subject to, and contingent upon, Officer's execution of a General
         Release Agreement in favor of the Company in substantially the form and
         substance as the one attached hereto as Schedule B.

         (e) Additional Provisions Applicable Upon Termination of
Employment Concurrent with or Following Change in Control. The following
provisions shall apply to any Termination of Employment occurring at the time
of, or at any time within one year following, a Change in Control.





             (1) Termination for Good Reason or Not for Cause. If
         the Termination of Employment (i) is the result of a dismissal or other
         action by the Company (but is not the result of Officer's Disability)
         and does not constitute a Termination for Cause, or (ii) is the result
         of a voluntary action by Officer (but is not the result of Officer's
         Normal Retirement) and constitutes a Termination for Good Reason, the
         Company shall pay the following amounts, and provide the following
         benefits, to Officer:

                       (A) The Base Salary (at the rate in effect on the date of
                  such Termination of Employment, as identified on Schedule A)
                  through and including the date of such Termination of
                  Employment, which amount shall be paid in cash on the date of
                  such Termination of Employment;

                       (B) A lump sum in cash equal to 2.99 times the sum of (i)
                  Officer's Base Salary (at the rate in effect on the date of
                  such Termination of Employment, as identified on Schedule A),
                  plus (ii) the greater of the then current year's targeted
                  bonus or actual bonus award (if applicable) for Officer, which
                  amount shall be paid in cash on the date of such Termination
                  of Employment;

                       (C) Any amount arising from Officer's participation in,
                  or benefits under, any Benefit Plan through and including the
                  date of such Termination of Employment, which amounts shall be
                  payable in accordance with the terms and conditions of such
                  Benefit Plan;

                       (D) For a period of one year following the date of such
                  Termination of Employment, a continuation of all health
                  insurance coverage applicable at the time of such Termination
                  of Employment to Officer and his immediate family under any
                  Benefit Plan; and

                       (E) With respect to a Termination of Employment described
                  in Section 5(e)(1)(i), an amount equal to one-twelfth (1/12)
                  of the Officer's Base Salary, which amount shall be paid in
                  cash on the date of such Termination of Employment.

             (2) Voluntary Termination Not for Good Reason. If the
         Termination of Employment is the result of a voluntary action by
         Officer, does not constitute a Termination for Good Reason and either
         (A) occurs at least six months, but not more than one year, following a
         Change in Control or (B) occurs at the time of, or at any time within
         one year following, a Change in Control and following the Company's
         requiring the Officer to perform his duties and responsibilities
         hereunder at a New Location, which relocation is not accepted by
         Officer within 30 days after receiving notice thereof, then the Company
         shall pay to Officer all amounts that would be payable pursuant to
         subsection (d)(2) of this Section had such Termination of Employment
         occurred prior to the Change in Control and constituted a Termination
         for Good Reason.

             (3)  Excise Tax and Gross-Up Payment.

                       (A) If any portion of such compensation
                  constitutes a parachute payment (a "Payment") and is subject
                  to the Excise Tax (hereinafter defined), then Company shall,
                  in addition to providing such compensation, pay the Gross-Up
                  Payment (hereinafter defined) to Officer in the manner
                  described below. For purposes of this Agreement, (i) "Excise
                  Tax" shall mean the tax imposed pursuant to section 4999 of
                  the Code and any interest or penalties incurred by the Officer
                  with respect to such Excise Tax, and (ii) "Gross-Up Payment"
                  shall mean, with respect to any compensation provided to the
                  Officer by Company (including without limitation the payments
                  provided for under this Agreement and any payments to the
                  Officer under any employee benefit plan, including without
                  limitation the Company's Long-term Incentive Plan, or other
                  arrangement) that is subject to the Excise Tax, an amount
                  that, after reduction of the amount of such Gross-Up Payment
                  for all federal, state, and local tax (including any interest
                  or penalties imposed with respect to such taxes) to which the
                  Gross-Up Payment is subject (including the Excise Tax to which
                  the Gross-Up Payment is subject), is equal to the amount of
                  the Excise Tax to which such compensation is subject. For
                  purposes of determining the amount of any Gross-Up Payment,
                  Officer shall be deemed to pay federal income taxes at the





                  highest marginal rate of taxation and state and local taxes,
                  if applicable, at the highest marginal rate of taxation in the
                  state and locality of residence of the Officer on the Date of
                  Termination, net of the maximum reduction in federal income
                  taxes that could be obtained from deduction of such state and
                  local taxes, if any.

                       (B) Subject to the provisions of subsection  5(e)(3)(C),
                  all  determinations  required to be made under this subsection
                  5(e)(3), including  whether and when a Gross-Up Payment is
                  required,  the amount of such Gross-Up Payment and the
                  assumptions to be utilized in arriving at such determination,
                  shall be made by the accounting firm which performed the audit
                  of the Company for the year preceding the year in which the
                  Change in Control  occurred (the  "Accounting  Firm") which
                  shall provide detailed  supporting  calculations  both to the
                  Company and the Officer within 15 business days of the receipt
                  of notice  from the Officer  that there has been a Payment, or
                  such  earlier  time as is  requested  by the Company.  In the
                  event that the Accounting  Firm is serving as accountant or
                  auditor for the  individual,  entity or group effecting the
                  Change in Control,  the Officer shall appoint another
                  nationally  recognized  accounting firm to  make the
                  determinations  required hereunder (which accounting firm
                  shall then be referred to as the Accounting Firm hereunder).
                  All fees and  expenses  of the  Accounting  Firm shall be
                  borne  solely by the  Company.  Any  Gross-Up Payment, as
                  determined pursuant to this subsection 5(e)(3),  shall be paid
                  by the Company to the Officer within five days of the receipt
                  of the Accounting Firm's determination.  If the Accounting
                  Firm determines that no Excise Tax is payable by the Officer,
                  it shall  furnish the Officer with a written  opinion that
                  failure to report the Excise Tax on the Officer's  applicable
                  federal income or excise tax return would not result in the
                  imposition of a negligence or similar penalty.  Any
                  determination by the Accounting Firm shall be binding upon the
                  Company and the Officer.

                       (C) The Officer  shall notify the Company in writing of
                  any claim by the Internal  Revenue  Service  that,  if
                  successful,  would require the payment by the  Company of the
                  Gross-Up  Payment.  Such notification  shall be given no later
                  than ten business days after the Officer is informed in
                  writing of such claim.  The Officer shall not pay such claim
                  prior to the  expiration  of the 30-day  period following  the
                  date on which it gives such  notice to the  Company  (or such
                  shorter  period  ending on the date that any  payment of taxes
                  with  respect to such claim is due).  If the  Company notifies
                  the Officer in writing prior to the  expiration of such period
                  that it desires to contest such claim,  (i) the Officer shall
                  accept legal  representation  with respect to such claim by an
                  attorney reasonably selected by the Company,  (ii) cooperate
                  with the Company in good faith in order to effectively contest
                  such claim, and (iii) permit the Company to participate in any
                  proceedings relating to such claim; provided,  however, the
                  Company shall bear and pay directly all costs and expenses
                  (including  legal and accounting fees and additional  interest
                  and penalties) incurred in connection with such contest and
                  shall indemnify and hold the Officer harmless, on an after-tax
                  basis, for any Excise Tax or income tax  (including  interest
                  and penalties  with respect  thereto)  imposed as a result of
                  such  representation  and  payment of costs and expenses. The
                  Company  shall  control  all  proceedings  taken in connection
                  with such contest to the extent relating  to issues impacting
                  whether a Gross-Up Payment is payable hereunder. The Officer
                  shall be entitled to settle or contest,  as the case may be,
                  any other issue  raised by the Internal Revenue Service or any
                  other taxing authority in connection with such contest.

                       (D) If any such claim  referred to in  subsection
                  5(e)(3)(C)  is made by the Internal Revenue Service and the
                  Company does not request the Officer to contest the claim
                  within the 30-day period  following  notice of the claim, the
                  Company shall pay to the Officer the amount of any Gross-Up
                  Payment owed to the Officer, but not previously paid pursuant
                  to subsection 5(e)(3)(B), immediately upon the  expiration of
                  such 30-day period.  If any such claim is made by the Internal
                  Revenue Service and the Company  requests the Officer to
                  contest such claim,  the Company shall pay to the Officer the
                  amount of any Gross-Up  Payment owed to the Officer,  but not
                  previously  paid under the  provisions of subsection
                  5(e)(3)(B),  within five days of a Final  Determination of the
                  liability of the Officer for such Excise Tax. For purposes of
                  this Agreement,  a "Final  Determination" shall be deemed to
                  occur with respect to a claim when (i) there is a decision,
                  judgment,  decree or other order by any court of competent
                  jurisdiction, which decision, judgment, decree or other order





                  has become final,  i.e., all allowable  appeals have been
                  exhausted by either party to the  action,  (ii)  there is a
                  closing agreement made under Section 7121 of the Code, or
                  (iii) the time for instituting a claim for refund has expired,
                  or if a claim was filed, the time for instituting suit with
                  respect thereto has expired.

             (4)  Letter of Credit. Following a Change in Control, Parent
         (within 10 days following receipt of Officer's written request
         therefor), at its sole cost and expense, shall post an irrevocable
         letter of credit with a banking institution reasonably acceptable to
         Officer in an amount equal to the maximum amount of the aggregate cash
         payments that would be made to Officer pursuant to the provisions of
         paragraph (1) of this subsection if the provisions of paragraph (1) of
         this subsection were to become applicable. Such letter of credit shall
         contain provisions making the funds available thereunder to Officer by
         Officer's drafts drawn at sight at any time and from time to time. Such
         provisions shall permit Officer to present drafts (including drafts for
         partial draws) drawn at sight by presentation by Officer to the
         applicable banking institution of a written statement to the effect
         that the Company is in default on a payment to be made to Officer
         pursuant to the terms of this Agreement (setting forth the amount of
         such payment in default) and that Officer is not in default under, and
         has not breached the terms of, this Agreement. Parent shall continue to
         keep such letter of credit in place until the expiration of at least 60
         days following the date of a Termination of Employment occurring after
         the Change in Control.

             (5)  Retirement Benefits Funded. Upon a Change in Control, any
         accrued but unfunded retirement benefit obligations to Officer under
         any then existing retirement plan shall be fully funded to a Rabbi
         Trust for the benefit of such Officer, which amount shall be paid in
         cash on the date of such Change in Control.

         (f) Certain Definitions. As used in the Section and elsewhere
in this Agreement, the following terms shall have the respective meanings
indicated:

             (1)  "Across-the-Board Salary Reduction" shall mean a reduction in
         the Base Salary that is a part of, and is at a rate consistent with, a
         reduction in the base salaries paid to substantially all officers of
         Parent.

             (2) "Change in Control" shall mean the occurrence of any of the
         following events:

                       (A) The  acquisition  by any  individual, entity or group
                  (within the meaning of Section  13(d)(3) or 14(d)(2) of the
                  Securities Exchange Act of 1934, as amended (the "Exchange
                  Act")) (a "Person") of beneficial  ownership  (within the
                  meaning of Rule 13d-3  promulgated  under the Exchange Act) of
                  20% or more of either (x) the then outstanding  shares of
                  common stock of Parent (the "Outstanding Parent Common Stock")
                  or (y) the combined  voting power of the then  outstanding
                  voting securities of Parent entitled to vote generally in the
                  election of directors (the "Outstanding  Parent Voting
                  Securities");  provided,  however,  that for purposes of this
                  subsection (A), the following  acquisitions  shall not
                  constitute a Change of Control: (i) any acquisition directly
                  from Parent, (ii) any acquisition by Parent, (iii) any
                  acquisition  by any employee benefit plan (or related trust)
                  sponsored or maintained by Parent or any corporation
                  controlled  by Parent or (iv) any  acquisition  by any
                  corporation  pursuant to a transaction  which  complies with
                  clauses (i), (ii) and (iii) of paragraph (C) below; or

                       (B) Members of the Incumbent Board cease for any reason
                  to constitute at least a majority of the Board; or

                       (C) Consummation of a  reorganization,  merger or
                  consolidation or sale or other  disposition of all or
                  substantially  all of the assets of Parent or an acquisition
                  of assets of another corporation (a "Business Combination"),
                  in each case, unless, following such Business Combination, (i)
                  all or substantially all of the individuals and entities who
                  were the beneficial owners, respectively, of the Outstanding
                  Parent Common Stock and Outstanding Parent Voting Securities
                  immediately prior to such Business Combination  beneficially
                  own, directly or indirectly,  more than 50% of, respectively,





                  the then outstanding shares of common stock and the combined
                  voting power of the then outstanding voting securities
                  entitled to vote generally in the election of directors,  as
                  the case may be, of the corporation resulting from such
                  Business  Combination  (including,  without limitation, a
                  corporation which as a result of such transaction owns Parent
                  or all or substantially all of Parent's assets either directly
                  or through one or more subsidiaries) in substantially the same
                  proportions  as their  ownership,  immediately  prior to such
                  Business Combination of the Outstanding  Parent Common Stock
                  and Outstanding  Parent Voting  Securities,  as the case may
                  be, (ii) no Person  (excluding any employee benefit plan (or
                  related trust) of Parent or the corporation  resulting from
                  such Business  Combination)  beneficially  owns,  directly or
                  indirectly,  20% or more of,  respectively,  the then
                  outstanding  shares of common stock of the  corporation
                  resulting  from such Business  Combination  or the combined
                  voting power of the then outstanding  voting securities of
                  such corporation except to the extent that such ownership
                  results solely from ownership of Parent that existed prior to
                  the Business Combination and (iii) at least a majority of the
                  members of the board of directors of the corporation resulting
                  from such Business Combination were members of the Incumbent
                  Board at the time of the execution of the initial agreement,
                  or of the action of the Board, providing for such Business
                  Combination; or

                       (D) Approval by the shareholders of Parent of a complete
                  liquidation or dissolution of Parent; or

                       (E) Consummation of a Business Combination not otherwise
                  constituting a Change of Control but, pursuant to which the
                  Person serving as Chief Executive Officer at the time of the
                  execution of the initial agreement is removed from, or
                  replaced in, such capacity with respect to the corporation
                  resulting from such Business Combination.

             (3) "Disability" shall mean Officer's physical or mental impairment
         or incapacity of sufficient severity that, in the opinion of the Board,
         either (A) Officer is unable to continue to perform his duties and
         responsibilities hereunder or (B) Officer's condition entitles him to
         disability benefits under any Benefit Plan providing for the payment
         thereof.

             (4) "Excessive Salary Reduction" shall mean (A) a reduction in the
         Base Salary that is not an Across-the-Board Salary Reduction (as
         defined in paragraph (1) of this subsection) and that, when combined
         with the net effect of all prior increases and reductions in the Base
         Salary (other than prior reductions that were Across-the-Board Salary
         Reductions), results in the Base Salary being less than 80% of the
         highest Base Salary to which Officer has ever been subject pursuant to
         this Agreement (as identified on Schedule A) or (B) a reduction in the
         Base Salary (whether or nor an Across-the-Board Salary Reduction) that,
         when combined with the net effect of all prior increases and reductions
         in the Base Salary (whether or not Across-the-Board Salary Reductions),
         results in the Base Salary being less than 65% of the highest Base
         Salary to which Officer has ever been subject pursuant to this
         Agreement (as identified on Schedule A).

             (5) "Incumbent Board' means the individuals who, as of the date of
         this Agreement, constitute the Board and any other individual who
         becomes a director of Parent after that date and whose election or
         nomination for election by Parent's shareholders was approved by a vote
         of at least a majority of the directors then comprising the Incumbent
         Board, but excluding, for this purpose, any such individual whose
         initial assumption of office occurs as a result of an actual or
         threatened election contest with respect to the election or removal of
         directors or other actual or threatened solicitation of proxies or
         consents by or on behalf of a Person other than the Incumbent Board.

             (6) "Normal Retirement' shall have the meaning given to such term
         in Section 1.27 of the Long-term Incentive Plan.

             (7) "Termination for Cause" shall mean a Termination of Employment
         as a result of a dismissal or other action by the Company following (A)
         Officer's continued failure to substantially perform his duties and
         responsibilities as described in Section 1 (other than any such failure
         resulting from Officer's physical or mental impairment or incapacity)





         after written demand for substantial performance is delivered by the
         Board or the Chief Executive Officer specifically identifying the
         manner in which the Board or the Chief Executive Officer, as the case
         may be, believes Officer has not substantially performed such duties
         and responsibilities, (B) Officer's engaging in misconduct that is
         materially injurious to the Company, monetarily or otherwise, or (C) a
         material violation by Officer of the provisions of Section 6. For
         purposes of clause (B) of this paragraph, an act, or failure to act, on
         Officer's part shall be considered "misconduct" if done, or omitted, by
         Officer not in good faith and without reasonable belief that such act,
         or failure to act, was in the best interest of the Company.

             (8)  "Termination for Good Reason" shall mean a Termination of
         Employment as a result of voluntary action by Officer within 30 days
         after receiving notice of (A) the demotion of the Officer to an officer
         position junior to the officer position specified in Section 1 or to a
         non-officer position, (B) an Excessive Salary Reduction (as defined in
         paragraph (4) of this subsection), or (C) the failure by Parent to
         obtain the assumption agreement described in Section 7(f) on or prior
         to a succession described in Section 7(f).

     6.  Nonpublic Information.

         (a)  Officer hereby acknowledges that, in connection with his
employment  with the Company,  he has  received,  and will  continue to receive,
various  information  regarding  the Company and its  business,  operations  and
affairs.  All such information,  to the extent not publicly available other than
as a result of a  disclosure  by  Officer in  violation  of this  Agreement,  is
referred to herein as the "Nonpublic Information."

         (b)  Officer hereby agrees that, from and after the date hereof and
continuing until three (3) years following a Termination of Employment,  he will
keep all  Nonpublic  Information  confidential  and will not,  without the prior
written  consent  of the  Board or the Chief  Executive  Officer,  disclose  any
Nonpublic  Information in any manner whatsoever or use any Nonpublic Information
other than in  connection  with the  performance  of his services to the Company
hereunder;  provided,  however, that the provisions of this subsection shall not
prevent  Officer from (1)  disclosing  any  Nonpublic  Information  to any other
employee of the Company or to any  representative  or agent of the Company (such
as an independent accountant, engineer, attorney or financial advisor) when such
disclosure is reasonably  necessary or  appropriate  (in Officer's  judgment) in
connection  with the  performance by Officer of his duties and  responsibilities
hereunder or (2) disclosing any Nonpublic  Information as required by applicable
law,  rule,  regulation  or legal  process (but only after  compliance  with the
provisions of subsection (c) of this Section).

         (c) If Officer is requested pursuant to, or required by, applicable
law,  rule,  regulation or legal process to disclose any Nonpublic  Information,
Officer  will notify  Parent  promptly so that the Company may seek a protective
order or other  appropriate  remedy or, in the Company's sole discretion,  waive
compliance  with the terms of this Section,  and Officer will fully cooperate in
any attempt by the Company to obtain any such protective  order or other remedy.
If no such protective  order or other remedy is obtained,  or the Company waives
compliance with the terms of this Section, Officer will furnish or disclose only
that  portion  of the  Nonpublic  Information  as is legally  required  and will
exercise all reasonable  efforts to obtain reliable  assurance that confidential
treatment will be accorded the Nonpublic Information that is so disclosed.

     7.  Miscellaneous Provisions.

         (a) Mitigation. Officer shall not be required to mitigate the
amount of any payment provided for in this Agreement by seeking other employment
or otherwise, and the amount of any payment provided for in this Agreement shall
not be reduced by any compensation earned by Officer as the result of employment
by another employer after the date of any Termination of Employment or
otherwise.

         (b) Interest. Until paid, all past due amounts required to be
paid by the Company to Officer under any provision of this Agreement shall bear
interest at the highest non-usurious rate permitted by applicable federal, state
or local law.

         (c) Equitable Relief Available. Officer acknowledges that
remedies at law may be inadequate to protect the Company against any actual or
threatened breach of the provisions of Section 6 by Officer. Accordingly,





without prejudice to any other rights or remedies otherwise available to the
Company, Officer agrees that the Company shall have the right to equitable and
injunctive relief to prevent any breach of the provisions of Section 6, as well
as to such damages or other relief as may be available to the Company by reason
of any such breach as does occur.

         (d) Breach Not a Defense. The representations and covenants on
the part of Officer contained in Section 6 shall be construed as ancillary to
and independent of any other provision of this Agreement, and the existence of
any claim or cause of action of Officer against the Company or any officer,
director, stockholder or representative of the Company, whether predicated on
this Agreement or otherwise, shall not constitute a defense to the enforcement
by the Company of the covenants on the part of Officer contained in Section 6.

         (e) Notices. Any notice or other communication called for by
the terms of this Agreement shall be in writing and either delivered personally
or by registered or certified mail (postage prepaid and return receipt
requested) and shall be deemed given when received at the following addresses
(or at such other address for a party as shall be specified by like notice):

             (1) If to Parent or the Company, 1400 Williams Square West, 5205
         North O'Connor Boulevard, Irving, Texas 75039, Attention: General
         Counsel.

             (2) If to Officer, the address of Officer set forth below Officer's
         signature on the signature page of this Agreement, and marked
         "Confidential."

         (f) Assumption by Successor of Parent. Parent shall require
any successor (whether direct or indirect) to all or substantially all of the
business or assets of Parent (whether by purchase of securities, merger,
consolidation, sale of assets or otherwise), by a written agreement in form and
substance satisfactory to Officer, to expressly assume and agree to perform the
obligations to be performed by Parent or the Company under this Agreement in the
same manner and to the same extent that Parent or the Company would be required
to perform if no such succession had taken place.

         (g)  Assignment

             (1) Except pursuant to an assumption by a successor
          described in subsection (f) of this Section, the rights and
          obligations of the Company pursuant to this Agreement may not be
          assigned, in whole or in part, by the Company to any other person or
          entity without the express written consent of Officer.

             (2) The rights and obligations of Officer pursuant
          to this Agreement may not be assigned, in whole or in part, by Officer
          to any other person or entity without the express written consent of
          the Board.

         (h) Successors. This Agreement shall be binding on, and shall inure to
the benefit of, the Company, Officer and their respective successors,  permitted
assigns, personal and legal representatives,  executors, administrators,  heirs,
distributees, devisees and legatees, as applicable.

         (i) Amendment and Waivers. Except as hereinafter provided, no provision
of this  Agreement  may be amended or  otherwise  modified,  and no right of any
party to this Agreement may be waived,  unless such  amendment,  modification or
waiver is agreed to in a written  instrument  signed by Officer  and Parent (and
any dated and signed Schedule A, as described in subsection (o) of this Section,
shall constitute such an instrument).  Beginning on the fifth anniversary of the
date  hereof,  unless a Change of Control  shall have  occurred or be pending or
contemplated, Parent may amend, modify, or waive any provision of, or terminate,
this  Agreement  upon sixty (60) days  notice  without  the  consent of Officer;
provided that any such amendment,  modification,  waiver or termination shall be
made to all  severance  agreements  of Parent  covering  all  officers of Parent
similarly  situated  to  Officer.  No  waiver  by  either  party  hereto  of, or
compliance with, any condition or provision of this Agreement to be performed by
the  other  party  hereto  shall be  deemed a waiver of  similar  or  dissimilar
provisions or conditions at the same or at any prior or subsequent time.





         (j) Complete Agreement. The provisions of this Agreement constitute the
complete  understanding  and  agreement  among the parties  with  respect to the
subject matter hereof, and no agreements or representations,  oral or otherwise,
express or implied,  with respect to the subject matter hereof have been made by
either party which are not set forth expressly in this Agreement.

         (k) Governing Law. THIS AGREEMENT IS BEING MADE AND EXECUTED IN, AND IS
INTENDED  TO BE  PERFORMED  IN,  THE  STATE OF  TEXAS  AND  SHALL  BE  GOVERNED,
CONSTRUED,  INTERPRETED AND ENFORCED IN ACCORDANCE WITH THE SUBSTANTIVE  LAWS OF
THE STATE OF TEXAS.

         (l) Attorney Fees. All legal fees and other costs incurred by
 Officer in connection with the resolution of any dispute or controversy under
 or in connection with this Agreement shall be reimbursed by the Company to
 Officer, if such dispute or controversy is resolved in favor of Officer. The
 Company shall be responsible for, and shall pay, all legal fees and other costs
 incurred by the Company in connection with the resolution of any dispute or
 controversy under or in connection with this Agreement, regardless of whether
 such dispute or controversy is resolved in favor of the Company or Officer.

         (m) Counterparts. This Agreement may be executed in several
counterparts, each of which shall be deemed to be an original, but all of which
together will constitute one and the same agreement.

         (n) Construction. The captions of the Sections, subsections and
paragraphs of this  Agreement  have been inserted as a matter of  convenience of
reference  only and shall not affect the meaning or  construction  of any of the
terms or provisions of this Agreement. Unless otherwise specified, references in
this  Agreement to a "Section,"  "subsection,"  "paragraph,"  "subparagraph"  or
"Schedule"  shall be considered to be  references  to the  appropriate  Section,
subsection,   paragraph,   subparagraph  or  Schedule,   respectively,  of  this
Agreement.  Unless  the  context  otherwise  requires,  all  words  used in this
Agreement in any gender shall include the masculine, feminine and neuter gender,
all singular  words shall  include the plural and all plural words shall include
the  singular.  As used in this  Agreement,  the  term  "including'  shall  mean
"including, but not limited to."

         (o) Schedule A. Schedule A may be replaced at any time and from time to
time to reflect a change in the Base Salary; provided, however, that no Schedule
A  attached  hereto  shall be  effective  unless it  contains a date and bears a
signature of approval on behalf of Officer and a signature of approval on behalf
of Parent; and provided further,  however, that if at any time two or more dated
and signed  copies of Schedule A conflict  with each  other,  the later dated of
such copies shall control.

         (p) Validity and Severability. If any term or provision of this
Agreement is held to be illegal,  invalid or unenforceable  under the present or
future  laws  effective  during  the term of this  Agreement,  (1) such  term or
provision  shall be fully  severable,  (2) this Agreement shall be construed and
enforced  as if such  term  or  provision  had  never  comprised  a part of this
Agreement and (3) the remaining  terms and  provisions of this  Agreement  shall
remain in full  force and  effect  and shall  not be  affected  by the  illegal,
invalid  or  unenforceable  term or  provision  or by its  severance  from  this
Agreement.  Furthermore,  in lieu of such illegal, invalid or unenforceable term
or provision,  there shall be added automatically as a part of this Agreement, a
term or provision as similar to such illegal,  invalid or unenforceable  term or
provision as may be possible and be legal, valid and enforceable.

         (q) Execution by Parent. The execution of this Agreement by Parent
shall  constitute an  acceptance  of, and an agreement to be bound by, the terms
and  provisions of this  Agreement by Parent and each of its direct and indirect
wholly-owned subsidiaries,  and Parent hereby agrees to cause each of its direct
and indirect wholly-owned  subsidiaries,  now and in the future, to fully comply
with all  obligations  applicable  to the Company  pursuant to the terms of this
Agreement.

         (r) Effect on Other Rights. Parker & Parsley Petroleum Company, a
Delaware  corporation  ("PPPC"),  and Officer have previously  entered into that
certain Severance  Agreement  effective January 1, 1996 (the "Original Severance
Agreement"). Effective as of the date hereof, PPPC has merged with and into MESA
Operating Co., a Delaware  corporation  and a direct wholly owned  subsidiary of
Parent ("Merger Sub"), with Merger Sub being the surviving entity of such merger
(the  "Merger").  Parent hereby  expressly  assumes and agrees to perform PPPC's





obligations under Section 5(e) of the Original  Severance  Agreement in the same
manner and to the same  extent  that PPPC  would be  required  to  perform  such
obligations, and Officer hereby acknowledges that the form and substance of such
assumption  is  satisfactory  to  Officer.  Each of Parent  and  Officer  hereby
acknowledges,  covenants and agrees that (i) the Merger constitutes a "Change in
Control" (as such term is defined in the Original Severance Agreement), (ii) the
terms and provisions of this Agreement are not intended to, shall not, and shall
not be deemed to, supersede,  limit or in any way affect any of Officer's rights
under  Section  5(e) of the  Original  Severance  Agreement  to receive  certain
payments  as a  result  of a  termination  of  Officer's  employment  with  PPPC
occurring  within one year  after  consummation  of the  Merger (a "MESA  Merger
Termination"), and (iii) other than as set forth in Section 5(e) of the Original
Severance Agreement,  Officer shall not be entitled to receive any payment under
this  Agreement  as a result of a MESA  Merger  Termination.  Parent and Officer
hereby agree that,  except for the rights,  duties and obligations of Parent and
Officer arising as a result of a MESA Merger Termination as set forth in Section
5(e) of the Original Severance  Agreement,  the Original Severance  Agreement is
hereby completely and irrevocably terminated in all respects effective as of the
date hereof,  and all terms and provisions of the Original  Severance  Agreement
other than Section 5(e) as such section  relates to the MESA Merger  Termination
are replaced and  superseded in all respects by the terms and provisions of this
Agreement.







                            (SIGNATURE PAGE ATTACHED)









     In witness whereof,  the parties have executed this Agreement  effective as
of the date first written above.


                        PIONEER NATURAL RESOURCES COMPANY



                        By:    /s/ Mark L. Withrow
                            -----------------------------------
                        Name:  Mark L. Withrow
                        Title: Executive Vice President



                        OFFICER:


                         /s/ Larry N. Paulsen
                        ---------------------------------------
                        Larry N. Paulsen

                        Address:

                        ---------------------------------------

                        ---------------------------------------








                 CONSENT OF PIONEER NATURAL RESOURCES USA, INC.

     Pioneer Natural Resources USA, Inc., a Delaware  corporation formerly named
MESA  Operating  Co. into which Parker & Parsley  Petroleum  Company was merged,
hereby consents to the partial termination,  replacement and supersession of the
Original  Severance  Agreement  (as  defined  in Section  7(r) of the  foregoing
Severance  Agreement)  to the extent  provided in Section 7(r) of the  foregoing
Severance Agreement.



                             PIONEER NATURAL RESOURCES USA, INC.


                             By:    /s/ Mark L. Withrow
                                 -------------------------------------
                             Name:  Mark L. Withrow
                             Title: Executive Vice President







                                   Schedule A

                     Attached to Severance Agreement between

                      Pioneer Natural Resources Company and
                                Larry N. Paulsen




BASE Salary:

         Effective Date                                     Amount

         January 1, 2005                                    $241,000.00





















Dated and Approved as of _______________:

PIONEER NATURAL RESOURCES COMPANY               OFFICER:


By:      /s/ Scott D. Sheffield                 /s/ Larry N. Paulsen
     ---------------------------------------    -----------------------------
Name:   Scott D. Sheffield                      Larry N. Paulsen
Title:  Chief Executive Officer and Chairman






                                   Schedule B

                            GENERAL RELEASE AGREEMENT


NOTICE:  Various  state and federal  laws and  regulations  prohibit  employment
discrimination  based on age,  race,  color,  religion,  sex,  national  origin,
disability,  citizenship,  and  membership or  application  for  membership in a
uniformed  service.  These  laws  are  enforced  through  the  Equal  Employment
Opportunity  Commission,  U.S.  Department of Labor,  Texas  Commission on Human
Rights,  and other federal and state  agencies.  You are advised to discuss this
release  with your  attorney.  In any event,  you should  thoroughly  review and
understand the effect of this document before signing it. Therefore, please take
this General Release Agreement home and carefully  consider it for at least five
days before signing it. In accordance with the requirements of the Older Workers
Benefit  Protection  Act, you are allowed at least 45 days from the date of your
receipt of this document and the accompanying explanatory letter to consider the
offer  made to you and to  return  an  executed  copy of this  form to the  Vice
President Administration.  Additionally,  after you have executed this form, you
have seven days to reconsider and revoke your agreement.

GENERAL RELEASE:  In consideration of my acceptance of the payments and benefits
offered to me under  Section  5(d)(2)(c) of the  Severance  Agreement,  I hereby
release and discharge Pioneer Natural Resources Company and its subsidiaries and
affiliates (the  "Company"),  and the officers,  directors,  employees,  agents,
successors,  and assigns of such entities  (collectively the "Released Parties")
from any and all claims,  liabilities,  demands,  and causes of action, known or
unknown, fixed or contingent,  which I have or claim against them as a result of
the  termination of my  employment,  including but not limited to claims arising
under  federal,  state,  or local laws  prohibiting  employment  discrimination,
including the Age Discrimination in Employment Act, or claims growing out of any
legal  restrictions,  contractual  or  otherwise,  on  the  Company's  right  to
terminate the employment of its  employees,  and I do hereby agree not to file a
lawsuit to assert such claims. I further acknowledge and agree that by accepting
the  Severance  Agreement  benefits,  I have  given  up my  right  to  file  any
complaint,  lawsuit,  or other legal action against any of the Released  Parties
growing out of,  connected  with, or relating in any way to my employment or the
termination of my employment with the Company.  Further in  consideration of the
payments and benefits offered to me under the Severance Agreement, I acknowledge
and agree that the  Released  Parties  may recover  from me any loss,  including
attorney's  fees and costs of  defending  against any claim  brought by me, that
they may suffer arising out of my breach of this General Release Agreement

     I understand that this General Release Agreement is final and binding,  and
I  agree  not  to  challenge   its   enforceability.   If  I  do  challenge  the
enforceability of this General Release Agreement, I agree initially to tender to
the Company all money received pursuant to the Severance  Agreement,  and invite
the  Company  to retain  such  money and agree  with me to cancel  this  General
Release  Agreement.  In the event the Company  accepts  this offer,  the Company
shall retain such money and this General Release  Agreement will be void. In the
event the Company  does not accept such offer,  the Company  shall so notify me,
and shall place such money in an  interest-bearing  escrow  account  pending the
resolution of any dispute as to whether this General Release  Agreement shall be
set aside and/or otherwise be rendered unenforceable.

     I acknowledge and agree that the Company has no legal obligation to provide
the payment under Section  5(d)(2)(c) of the Severance  Agreement offered to me,
and my  acceptance  of the  obligations  and  attendant  additional  payment  as
described therein constitutes my agreement to all terms and conditions set forth
in this General Release Agreement,  and are in consideration of the promises and
undertakings  of the Company  pursuant  to the  Severance  Agreement.  I further
acknowledge and agree that for unemployment  compensation purposes, the payments
I receive under the Severance Agreement shall be considered  additional wages in
lieu  of  notice;  and  that,  accordingly,  I  may  be  ineligible  to  receive
unemployment compensation benefits for an equivalent period of time.

     This General Release  Agreement does not have any effect on any claim I may
have against the Released Parties  unrelated to the termination of my employment
or with  respect  to any  rights  or claims  that may arise  after the date this
General Release Agreement is executed.

     I have  carefully  read and fully  understand all of the provisions of this
General Release.  I further  acknowledge that entering into this General Release
Agreement is knowing and voluntary on my part, that I have had a reasonable time
to deliberate regarding its terms, and that I have had the right to consult with
an attorney if I so desired.

     I  acknowledge  that I  initially  executed  a General  Release  Agreement,
containing the same terms and conditions as this General Release Agreement, more
than seven days prior to the date appearing below and placed the General Release
Agreement in the mail  addressed to the Company.  I further  acknowledge  that I
have had at least  seven  days  since the date of  execution  of the  originally
executed  General  Release  Agreement  in  which to  reconsider  and  revoke  my
agreement  to the  terms  and  conditions  set  forth  in this  General  Release
Agreement.


Date signed:
              -----------------          ------------------------------------
                                         Signature of Officer

Date signed:
              -----------------          ------------------------------------
                                         Signature of Officer