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                       SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549

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                                    FORM 8-A



                FOR REGISTRATION OF CERTAIN CLASSES OF SECURITIES
                     PURSUANT TO SECTION 12(b) OR (g) OF THE
                         SECURITIES EXCHANGE ACT OF 1934


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                        PIONEER NATURAL RESOURCES COMPANY
             (Exact name of registrant as specified in its charter)



                                                              
               DELAWARE                                          75-2702753
(State of incorporation or organization)         (I.R.S. Employer Identification Number)


         1400 WILLIAMS SQUARE WEST
           5205 N. O'CONNOR BLVD.                                   75039
               IRVING, TEXAS                                     (Zip Code)
   (Address of principal executive offices)

If this form relates to the registration of   If this form relates to the registration of
a class of securities pursuant to Section     a class of securities pursuant to Section
12(b) of the Exchange Act and is effective    12(g) of the Exchange Act and is effective
pursuant to General Instruction A.(c),        pursuant to General Instruction A.(d),
please check the following box. [X]           please check the following box. [ ]




Securities to be registered pursuant to Section 12(b) of the Act:




          Title of each class                                    Name of each exchange or which
          to be so registered                                    each class is to be registered
          -------------------                                    ------------------------------
                                                              
 RIGHTS TO PURCHASE SERIES A JUNIOR PARTICIPATING PREFERRED
             STOCK, PAR VALUE $.01 PER SHARE                     NEW YORK STOCK EXCHANGE




Securities to be registered pursuant to Section 12(g) of the Act: None



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ITEM 1. DESCRIPTION OF REGISTRANT'S SECURITIES TO BE REGISTERED.

         On July 19, 2001, the board of directors of Pioneer Natural Resources
Company (the "Company") declared a dividend of one preferred share purchase
right (a "Right") for each outstanding share of common stock, par value $0.01
per share (the "Common Shares"), of the Company and each outstanding
exchangeable shares of Pioneer Natural Resources (Canada) Ltd., an Alberta
corporation and a wholly-owned indirect subsidiary of the Company (the
"Exchangeable Shares" and together with the Common Shares, the "Capital Stock").
The dividend is payable on July 31, 2001 (the "Record Date") to the holders of
Capital Stock of record on that date. Each Right entitles the registered holder
to purchase from the Company one one-thousandth of a share of Series A Junior
Participating Preferred Stock, par value $0.01 per share (the "Preferred
Shares"), of the Company at a price of $95.00 per one one-thousandth of a
Preferred Share (the "Purchase Price"), subject to adjustment. The description
and terms of the Rights are set forth in a Rights Agreement dated as of July 20,
2001 (the "Rights Agreement"), between the Company and Continental Stock
Transfer & Trust Company, as Rights Agent (the "Rights Agent").

         Until the earlier to occur of (i) the tenth business day following a
public announcement that (A) a person (other than Southeastern Asset Management,
Inc. or any of its affiliates or associates (the "Southeastern Group") or a
permitted transferee of the Southeastern Group) has acquired beneficial
ownership of 15% or more of the outstanding Capital Stock, or (B) the
Southeastern Group has become the beneficial owner of one Capital Stock in
excess of the greater of (1) the lesser of (a) the percentage of Capital Stock
beneficially owned by the Southeastern Group as of the date of the Rights
Agreement or (b) the lowest percentage of Capital Stock beneficially owned by
the Southeastern Group thereafter or (2) 15% of the outstanding Capital Stock
(in either case, an "Acquiring Person") or (ii) the tenth business day (subject
to extension) after a person commences, or announces its intention to commence,
a tender offer or exchange offer the consummation of which would result in any
person becoming the beneficial owner of the number of shares necessary to be an
Acquiring Person (the earlier of such dates being called the "Distribution
Date"), the Rights will be evidenced, with respect to any of the Common Share or
Exchangeable Share certificates outstanding as of the Record Date, by such
Common Share or Exchangeable Share certificates with a copy of this Summary of
Rights attached thereto. The Rights Agreement provides that, until the
Distribution Date, the Rights will be transferred with and only with the Capital
Stock. Until the Distribution Date (or earlier redemption or expiration of the
Rights), new Capital Stock certificates issued after the Record Date, upon
transfer or new issuance of Capital Stock will contain a notation incorporating
the Rights Agreement by reference. Until the Distribution Date (or earlier
redemption or expiration of the Rights), the surrender for transfer of any
certificates for Capital Stock, outstanding as of the Record Date, even without
such notation or a copy of this Summary of Rights being attached thereto, will
also constitute the transfer of the Rights associated with the Capital Stock
represented by such certificate.

         As soon as practicable following the Distribution Date, separate
certificates evidencing the Rights ("Right Certificates") will be mailed to
holders of record of the Capital Stock as of the close of business on the
Distribution Date and such separate Right Certificates alone will evidence the
Rights.

         The Rights are not exercisable until the Distribution Date. The Rights
will expire on July 31, 2011 (the "Final Expiration Date"), unless the Final
Expiration Date is extended or unless the Rights are earlier redeemed by the
Company, in each case, as described below.

         The Purchase Price payable, and the number of Preferred Shares or other
securities or property issuable, upon exercise of the Rights are subject to
adjustment from time to time to prevent dilution (i) in the event of a stock
dividend on, or a subdivision, combination or reclassification of, the Preferred
Shares, (ii) upon the grant to holders of the Preferred Shares of certain rights
or warrants to subscribe for or purchase Preferred Shares at a price, or
securities convertible into Preferred Shares with a conversion price, less than
the then current market price of the Preferred Shares or (iii) upon the
distribution to holders of the Preferred Shares of evidences of indebtedness or
assets (excluding regular periodic cash dividends paid out of earnings or
retained earnings or dividends payable in Preferred Shares) or of subscription
rights or warrants (other than those referred to above).

         The number of outstanding Rights and the number of one one-thousandths
of a Preferred Share issuable upon exercise of each Right are also subject to
adjustment in the event of a stock split of the Common Shares or a stock
dividend on the Common Shares payable in Common Shares or subdivisions,
consolidations or combinations of the Common Shares occurring, in any such case,
prior to the Distribution Date.



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         Preferred Shares purchasable upon exercise of the Rights are not
redeemable. Each Preferred Share will be entitled to a minimum preferential
quarterly dividend payment of $1.00 per share but will be entitled to an
aggregate dividend of 1,000 times the dividend declared per Common Share. In the
event of liquidation, the holders of the Preferred Shares will be entitled to a
minimum preferential liquidation payment of $1,000 per share plus an amount
equal to accrued and unpaid dividends thereon but will be entitled to an
aggregate payment of 1,000 times the payment made per Common Share. Each
Preferred Share will have 1,000 votes, voting together with the Common Shares.
Finally, in the event of any merger, consolidation or other transaction in which
Common Shares are exchanged, each Preferred Share will be entitled to receive
1,000 times the amount received per Common Share. These rights are protected by
customary antidilution provisions.

         Because of the nature of the Preferred Shares' dividend, liquidation
and voting rights, the value of the one one-thousandth interest in a Preferred
Share purchasable upon exercise of each Right should approximate the value of
one Common Share.

         In the event that, after a person or a group has become an Acquiring
Person, the Company is acquired in a merger or other business combination
transaction or 50% or more of its consolidated assets or earning power are sold
or transferred (subject to certain exceptions), proper provision will be made so
that each holder of a Right will thereafter have the right to receive, upon the
exercise thereof at the then current exercise price of the Right, that number of
shares of common stock of the acquiring company which at the time of such
transaction will have a market value of two times the exercise price of the
Right. In the event that any person becomes an Acquiring Person, proper
provision shall be made so that each holder of a Right, other than Rights
beneficially owned by the Acquiring Person (which will thereafter be void), will
thereafter have the right to receive upon exercise that number of Common Shares
having a market value of two times the exercise price of the Right.

         At any time after a person or group has become an Acquiring Person and
prior to the acquisition by such person or group of 50% or more of the
outstanding Capital Stock, the board of directors of the Company may exchange
the Rights (other than Rights owned by such person or group which have become
void), in whole or in part, at an exchange ratio of one Common Share for each
two Common Shares for which each Right is then exercisable pursuant to the
provisions of the Rights Agreement (subject to adjustment).

         With certain exceptions, no adjustment in the Purchase Price will be
required until cumulative adjustments require an adjustment of at least 1% of
such Purchase Price. No fractional Preferred Shares will be issued (other than
fractions which are integral multiples of one one-thousandth of a Preferred
Share, which may, at the election of the Company, be evidenced by depositary
receipts) and in lieu thereof, an adjustment in cash will be made based on the
market price of the Preferred Shares on the last trading day prior to the date
of exercise.

         At any time prior to such time as a person or group becomes an
Acquiring Person, the board of directors of the Company may redeem the Rights in
whole, but not in part, at a price of $0.001 per Right (with respect to each
holder of Rights, rounded up to the nearest cent for the aggregate Rights held
by such holder) (the "Redemption Price"). The redemption of the Rights may be
made effective at such time on such basis and with such conditions as the board
of directors of the Company in its sole discretion may establish. Immediately
upon any redemption of the Rights, the right to exercise the Rights will
terminate and the only right of the holders of Rights will be to receive the
Redemption Price.

         The terms of the Rights may be amended by the board of directors of the
Company without the consent of the holders of the Rights, including an amendment
to lower certain thresholds described above to not less than the greater of (i)
the sum of .001% and the largest percentage of the outstanding Capital Stock
then known to the Company to be beneficially owned by any person or group of
affiliated or associated persons (subject to certain exceptions) and (ii) 10%,
except that from and after such time as any person or group of affiliated or
associated persons becomes an Acquiring Person no such amendment may adversely
affect the interests of the holders of the Rights.

         Until a Right is exercised, the holder thereof, as such, will have no
rights as a stockholder of the Company, including the right to vote or to
receive dividends.



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         A copy of the Rights Agreement has been filed with the Securities and
Exchange Commission as an exhibit to this Registration Statement on Form 8-A.
This summary description of the Rights does not purport to be complete and is
qualified in its entirety by reference to the Rights Agreement.

ITEM 2. EXHIBITS.

4.1.     Rights Agreement, dated as of July 20, 2001, between the Company and
         Continental Stock Transfer & Trust Company, as Rights Agent, specifying
         the terms of the Rights, which includes the form of Certificate of
         Designation of Series A Junior Participating Preferred Stock as Exhibit
         A, the form of Right Certificate as Exhibit B and the form of the
         Summary of Rights to Purchase Preferred Shares as Exhibit C.




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                                    SIGNATURE

         Pursuant to the requirements of Section 12 of the Securities Exchange
Act of 1934, the registrant has duly caused this registration statement to be
signed on its behalf by the undersigned, thereto duly authorized.


                                       PIONEER NATURAL RESOURCES COMPANY



Date:  July 20, 2001                   By:      /s/ Mark L. Withrow
                                           -------------------------------------
                                       Name:  Mark L. Withrow
                                       Title:    Executive Vice President



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                                  EXHIBIT INDEX


      
4.1.     Rights Agreement, dated as of July 20, 2001, between the Company and
         Continental Stock Transfer & Trust Company, as Rights Agent, specifying
         the terms of the Rights, which includes the form of Certificate of
         Designation of Series A Junior Participating Preferred Stock as Exhibit
         A, the form of Right Certificate as Exhibit B and the form of the
         Summary of Rights to Purchase Preferred Shares as Exhibit C.