EXHIBIT 10.1


                               UNOCAL CORPORATION

                      2000 EXECUTIVE STOCK PURCHASE PROGRAM

     The purpose of the 2000 Executive Stock Purchase Program (the "Program") is
to promote the long-term growth and financial success of Unocal Corporation (the
"Company") by (1)  providing a means  whereby  executives of the Company and its
subsidiaries  can acquire and maintain stock  ownership,  thereby  strengthening
their  commitment to maximizing  the value of the Company for its  stockholders,
while (2) placing them at risk in the event of poor Company  performance through
the use of full recourse promissory notes as payment for Company stock.


1.   General Description

     The  Program  provides  an  opportunity  for the  Company's  executives  to
purchase up to 1.75 million  shares of Stock of the Company and to receive loans
from the Company to finance such purchases.


2.   Definitions

     The following  definitions  shall be applicable  throughout the Program but
shall not be  deemed to apply in other  contexts  unless  specifically  provided
otherwise:

     a. "Award" means (i) an award  permitting a Participant  to purchase  Stock
from the Company  under this Program at the Purchase  Price,  together  with the
related  Purchase  Loan, or (ii) an award  offering to make a Purchase Loan to a
Participant  for the purchase of Stock on a specified  date or dates in the open
market, directly from the Company, or by private purchase.

     b. "Award  Agreement" means a written  agreement  between the Company and a
Participant which sets forth the terms of an Award. Award Agreements need not be
identical and shall be in the form approved by the Committee.

     c.  "Board"  means the Board of  Directors  of the  Company,  except  those
members who are Employees.

     d.  "Cause"  means (i)  conduct or action by a  Participant  which,  in the
opinion of the  Committee,  is materially  harmful to the Company;  (ii) willful
failure by a  Participant  to follow an order of the Board,  except in such case
where the Participant  believes in good faith that following such order would be
materially  detrimental to the interests of the Company;  (iii) a  Participant's
conviction  of a felony;  or (iv)  performance  by a Participant  which,  in the
opinion  of the  Committee,  falls  below  the  reasonable  expectations  of the
Company.

     e.  "Code"  means the Internal Revenue Code of 1986, as amended.

     f. "Committee" means the Management  Development and Compensation Committee
of the Board, which shall consist solely of two or more directors who qualify as
"outside  directors," as defined in the regulations under Section 162 (m) of the
Code and as "Non-Employees Director" as defined in Rule 16b-3.

     g.  "Company"  means Unocal Corporation.

     h.  "Date of Grant"  means the date on which  the  granting  of an Award is
authorized  by the  Committee  or such  later  date as may be  specified  by the
Committee in such authorization.

     i. "Disability"  means the inability of a Participant to perform his or her
normal  duties of  employment  as a result of physical or mental  incapacity  as
determined by the Committee.

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     j.  "Employee"  means any person  regularly  employed  by the  Company or a
Subsidiary on a full-time salaried basis.

     k. "Fair  Market  Value"  means the  average of the  reported  high and low
prices  of the  Stock as  reported  in the New  York  Stock  Exchange  Composite
Transactions  quotations  on a specified  date or the actual  purchase  price of
shares acquired by the Participant under the Program.

     l.  "Interest  Rate" means the interest rate  determined by the  Committee,
which shall be the lowest rate which avoids the imputation of interest under the
Code at the time of the Loan.

     m.  "Participant"  means an Employee of the Company or a Subsidiary who has
been granted an Award under the Program.

n.  "Purchase  Date"  means the date or dates on which a  Participant  purchases
shares of Stock pursuant to an Award.

     o.  "Purchase  Loan" means an extension of credit to a  Participant  by the
Company evidenced by the Purchase Note.

     p.  "Purchase  Note" means a full recourse  promissory  note  including the
terms set forth in Section 8.

     q. "Purchase  Price" means (i), in the case of a purchase of Stock from the
Company, the Fair Market Value of the Stock on the Purchase Date or (ii), in the
case of a purchase  of Stock in the open  market or from a party  other than the
Company,  the price at which the  Participant  purchases  Stock  pursuant  to an
Award.

     r.  "Retirement"  means  termination  of  employment  on or  after  "normal
retirement age" as defined in the Company's retirement plan then in effect.

     s. "Rule  16b-3"  means Rule 16b-3 as  promulgated  by the  Securities  and
Exchange Commission pursuant to the Securities Exchange Act of 1934, as amended.

     t. "Stock"  means shares of common stock of the Company as described in the
Company's Certificate of Incorporation.

     u.  "Subsidiary"   means  any  corporation  of  which  a  majority  of  the
outstanding  voting  stock or voting  power is  beneficially  owned  directly or
indirectly by the Company.

     v.  "Voluntary  Termination"  means  any  termination  of  employment  by a
Participant  prior to  Retirement  other than a  termination  without Cause or a
termination due to death or Disability.


3.   Effective Date and Duration

     The Program  shall be effective on March 16, 2000,  subject to the approval
of this Program by the Company's  stockholders.  If this Program is not approved
by the Company's  stockholders,  Participants must sell to the Company the Stock
purchased  under this  Program at the lesser of the  Purchase  Price or the Fair
Market  Value on the date of such sale,  and each  Purchase  Loan  shall  become
immediately due and payable in full (including accrued and unpaid interest).  If
this Program is approved by the Company's  stockholders,  it shall  terminate on
December 31, 2003;  provided that  Purchase  Loans  outstanding  as of such date
shall not be affected or impaired by termination of the Program.

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4.   Administration

     The Committee shall  administer the Program.  The acts of a majority of its
members present at any meeting at which a quorum is present and acts unanimously
approved in writing by the Committee  shall be deemed the acts of the Committee.
The Committee may conduct meetings in person or by telephone.
     No member of the  Committee,  while  serving as such,  shall be eligible to
receive an Award under the  Program.  The  Committee  shall have the  authority,
subject to the provisions of the Program,  to establish,  adopt,  or revise such
rules  and  regulations  and to make all  such  determinations  relating  to the
Program as it may deem  necessary  or  advisable  in the  administration  of the
Program. Among other things, the Committee shall have the authority,  subject to
the terms of the Program,  to determine (a) the  individuals  to whom the Awards
are  granted,  (b) the time or times the Awards are  granted,  (c) the  Purchase
Dates  for  such  Awards,  (d) the  basis  for any  termination  of  employment,
including whether or not it was for Cause,  Disability,  Retirement or otherwise
(which  determination  shall  be  reasonable),  and (e)  the  forms,  terms  and
provisions of the Award Agreement and any other documents under the Program. The
Committee's interpretation of the Program or any Awards granted pursuant thereto
and all  decisions  and  determinations  by the  Committee  with  respect to the
Program shall be final, binding, and conclusive on all parties.


5.   Shares Subject to the Program

     The Committee  may,  from time to time,  grant and amend Awards to eligible
Employees in  accordance  with the  provisions of the Plan;  provided,  however,
that:

     a.  Subject to Section  10,  the  aggregate  number of shares of Stock made
subject  to Awards  under  this Plan may not  exceed  1,750,000  shares,  and no
Participant shall receive an Award with respect to more than 200,000 shares.

     b. If a Participant fails to purchase all of the shares of Stock subject to
an Award,  such  unpurchased  shares of Stock  shall  again be  available  to be
granted as an Award under this Program.

     c. Stock purchased under this Program may be from the Company's  authorized
and unissued Stock or Treasury  Shares;  Stock purchased on the open market;  or
Stock acquired by private purchase.


6. Eligibility

     Senior   management  and  other  key  Employees  of  the  Company  and  its
Subsidiaries  (including  officers  or  Employees  who are members of the Board)
shall be eligible to be granted Awards under this Program.


7. Stock Purchase

     a. Grant of Award.  The Committee shall determine the Purchase Date and, in
the case of an Award  permitting  the  Participant  to  purchase  Stock from the
Company,  the number of shares of Stock that the  Participant may purchase under
the Award or, in the case of an Award  offering  to make a  Purchase  Loan for a
purchase in the open market or from a third  party,  the amount of the  Purchase
Loan.  The Committee  shall give each  Participant  written  notice prior to the
Purchase Date stating (i) the maximum and minimum  numbers (which numbers may be
identical) of shares of Stock that the  Participant may purchase under the Award
or the maximum and  minimum  amounts  (which  amounts may be  identical)  of the
Purchase  Loan,  (ii) the Purchase  Date and (iii) the  Interest  Rate and other
terms pertaining to the Purchase Loan.

     b. Exercise of Award.  A Participant  shall exercise an Award by delivering
to the Company on the  Purchase  Date (i) a notice  stating the number of shares
(not less than the minimum number and not more than the maximum number specified
in the Award) such  Participant  elects to purchase or the amount (not less than
the minimum and not more than the maximum  amount  specified  in the Award) that
the

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Participant  elects to borrow,  and (ii) an executed Award  Agreement,  Purchase
Note and any other documents  required pursuant to the Program.  Any Participant
who does not elect to purchase at least the minimum  number of shares  specified
in the Award Agreement or to borrow at least the minimum amount specified in the
Award  Agreement on the Purchase Date shall forfeit any rights under the Program
with respect to such Award, including,  without limitation, any right to receive
a Purchase Loan.


8.   Purchase Loans

     a. General.  The Company shall extend a Purchase Loan to a Participant upon
exercise  of an Award  subject  to the  terms and  conditions  set forth in this
Section 8. The original  principal amount of the Purchase Loan shall be equal to
the total purchase price of the Stock.  Such Purchase Loan shall be evidenced by
a Purchase Note with full recourse  against the maker.  The  obligations of each
Participant  under the Purchase  Loan shall be  unconditional  and absolute and,
without  limiting  the  generality  of the  foregoing,  shall  not be  released,
discharged or otherwise  affected by any change in the  existence,  structure or
ownership of the Company, or any insolvency, bankruptcy, reorganization or other
similar  proceeding  affecting  the Company or its assets or the market value of
the Stock or any resulting release or discharge of any obligation of the Company
or the existence of any claim, set-off or other rights which any Participant may
have at any time against the Company or any other person,  whether in connection
with the  Program or with any  unrelated  transactions,  provided  that  nothing
herein  shall  prevent  the  assertion  of any such  claim by  separate  suit or
counterclaim.

     Notwithstanding  anything to the  contrary  in this  Section 8, the Company
shall not be required to make any Purchase Loan to a  Participant  if the making
of such  Purchase  Loan will (i) cause the  Company to violate  any  covenant or
similar provision in any indenture,  loan agreement or other agreement,  or (ii)
violate any applicable federal,  state or local law, provided,  that the failure
to make such Purchase Loan shall be deemed to revoke the acceptance and exercise
of  a  related   Award   unless   otherwise   specified   by  the   Participant.
Notwithstanding  anything  to the  contrary  in this  Section  8, the  terms and
repayment  provisions  of the Purchase  Note shall  conform with the  applicable
rules and regulations of the Federal Reserve Board then in effect.

     b.  Unsecured  Loan.  Payment of the  Purchase  Loan shall not be  secured,
directly  or  indirectly,  by a pledge of the  shares of Stock  acquired  by the
Participant upon the exercise of the Award to which the Purchase Loan relates.

     c.  Interest.  Interest on the principal  balance of the Purchase Loan will
accrue  annually,  in arrears,  at the Interest Rate.  Except as provided in the
Purchase Loan and related Purchase Note,  interest shall be added to the balance
of the Purchase  Loan. To the extent that a Participant  receives cash dividends
or other  distributions paid in cash on Stock purchased under this Program,  the
Participant  shall prepay the related Purchase Loan with the full pre-tax amount
of such dividend or distribution  received within ten (10) days of receipt. Such
prepayments  shall first be applied to pay accrued interest on the Purchase Loan
and then to reduce the principal balance due on the Purchase Loan.

     d. Term. The term of the Purchase Loan for any  Participant  shall begin on
such Participant's  Purchase Date and, subject to prepayment as provided in this
Section 8, shall have a final  maturity date on the eighth (8th)  anniversary of
the Purchase Date.

     e.  Payment  Schedule.  Except as  provided  in Section  3, and  subject to
prepayment  as provided in this  Section 8, no payments of either  principal  or
interest  shall be due under the  Purchase  Loan during the first five (5) years
following  the  Purchase  Date.  The  principal  balance  of the  Purchase  Loan
(including  accrued  but  unpaid  interest)  outstanding  after any  prepayments
following the end of such five-year  period,  if any (the "Remaining  Balance"),
shall be  payable in three (3) equal  annual  installments  on the sixth  (6th),
seventh (7th) and eighth (8th) anniversaries of the Purchase Date, with interest
on the unpaid  Remaining  Balance  payable  annually  in  arrears,  on each such
anniversary.

     f. Optional Prepayments. A Participant may prepay all or any portion of the
Purchase Loan at any time. Any prepayments  made to the Company pursuant to this
Section 8(f) shall first be applied to pay

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accrued  interest on the Purchase Loan and then to reduce the principal  balance
due on the Purchase  Loan.  Any  prepayment  of the balance of the Purchase Loan
shall be applied to the principal payments due thereon in chronological order of
maturity.

     g.  Prepayment  Obligations  Upon Voluntary  Termination or Termination for
Cause.  Upon a termination of employment  that is determined by the Committee to
be a termination for Cause or a Voluntary  Termination,  any outstanding balance
on the Purchase Loan  (including any accrued and unpaid  interest)  shall become
due and  payable  on the 60th day  following  such  termination  of  employment.
Prepayment  of a Purchase  Loan shall not be  required in the event of any other
termination  of  employment  (including  termination  due to death,  Disability,
Retirement, and termination without Cause).

     h. Purchase Loan Forgiveness.  For Awards granted during the year 2000, the
Committee shall provide for the partial  forgiveness of the Purchase Loan in the
case of a  Participant  who has died or becomes  Disabled to the extent that, at
the maturity date of the Purchase Loan, the outstanding  balance of the Purchase
Loan (including any accrued and unpaid interest), increased by the amount of any
repayments of principal previously made by the Participant,  is greater than the
sum of (i) the Fair Market  Value of the number of shares of Stock  purchased by
the  Participant  pursuant to the  exercise of the Award plus (ii) the amount of
the Performance Bonus paid to the Participant under the Long-Term Incentive Plan
of 1998 for the  four-year  award period  ending on December 31, 2003 plus (iii)
interest on such  Performance  Bonus at the Interest Rate from December 31, 2003
to the repayment date.


9.   General

     a.  Government  and Other  Regulations.  The obligation of the Company with
respect to the grant and exercise of Awards  shall be subject to all  applicable
laws, rules, and regulations,  and to such approvals by governmental agencies as
may be required.  The Company shall be under no obligation to register under the
Securities  Act of 1933,  as amended  ("Act") any of the shares of Stock  issued
under  the  Program.  If the  Stock  issued  under the  Program  may in  certain
circumstances  be exempt  from  registration  under  the Act,  the  Company  may
restrict  the  transfer of such shares in such manner as it deems  advisable  to
ensure the availability of any such exemption.

     b. Tax Withholding. The Company or a Subsidiary, as appropriate, shall have
the right to deduct from any  benefits  due under the  Program or other  amounts
payable to a Participant an amount  sufficient to satisfy any federal,  state or
local withholding  requirements  applicable to such benefits.  In addition, as a
condition  to payment or delivery of any benefit  hereunder,  including  without
limitation,  any  forgiveness  of any  portion of a Purchase  Loan  pursuant  to
Section 3 or Section 8(h),  the Company or a  Subsidiary,  as  appropriate,  may
require a  Participant  to pay to the  Company or  Subsidiary  the amount of any
applicable federal, state or local withholding taxes.

     c. Claim to Awards and Employment Rights. No Employee or other person shall
have any claim or right to be granted an Award under the  Program.  Neither this
Program nor any action taken hereunder shall be construed as giving any Employee
any right to be retained in the employ of the Company or a Subsidiary.

     d. Applicable Law. This Program, any Award Agreements and all other related
documents  shall be governed by and construed in accordance with the laws of the
State of California  without regard to the  application of the conflicts of laws
provisions  thereof  except  for such  matters  as are  subject  to the  General
Corporation Law of Delaware.

     e. Inurement of Rights and  Obligations.  The rights and obligations  under
the Program and any related Award  Agreements shall inure to the benefit of, and
binding upon, the Company,  its successors and assigns, and the Participants and
their beneficiaries.

     f.  Non-exclusivity  of Program.  Nothing in this Program shall limit or be
deemed to limit the  authority of the Board or the  Committee to grant awards or
authorize any other compensation,  with or without reference to Stock, under any
other plan or authority.

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     g. Severability;  Validity.  This Program is intended to qualify under Rule
16b-3.  If any of the terms or  provisions  of this  Program  conflict  with the
requirements  of Rule  16b-3,  then such  terms and  provisions  shall be deemed
inoperative to the extent they so conflict with such requirements.  In the event
that any  provision  of the  Program or any  related  Award  Agreement  or other
related document is held to be invalid,  void or  unenforceable,  the same shall
not affect,  in any respect  whatsoever,  the validity of any other provision of
the Program or any related Award Agreement or other document.

     h.  Indemnification.  Each person who is or shall have been a member of the
Committee or the Board,  including the Employee directors,  shall be indemnified
and held harmless by the Company against and from any loss, cost, liability,  or
expense that may be imposed  upon or  reasonably  incurred by him in  connection
with or resulting from any claim, action, suit, or proceeding to which he may be
a party or in which he may be involved by reason of any action or failure to act
under  the  Program  and  against  and from any and all  amounts  paid by him in
satisfaction of judgment in any such action,  suit or proceeding against him. He
shall give the Company an opportunity,  at its own expense, to handle and defend
the same before he  undertakes  to handle and defend it on his own  behalf.  The
foregoing right of indemnification shall not be exclusive of any other rights of
indemnification  to which  such  persons  may be  entitled  under the  Company's
Certificate of Incorporation or Bylaws, as a matter of law, or otherwise, or any
power that the Company may have to indemnify them or hold them harmless.

     i.  Reliance  on  Reports.  Each  member of the  Committee  and the  Board,
including the Employee directors,  shall be fully justified in relying or acting
in good faith upon any report made by the independent  public accountants of the
Company  and its  Subsidiaries  and  upon any  other  information  furnished  in
connection  with the Program by any person or persons other than himself.  In no
event shall any person who is or shall have been a member of the Committee or of
the Board be liable  for any  determination  made or other  action  taken or any
omission  to act in  reliance  upon any such  report or  information  or for any
action taken, including the furnishing of information,  or failure to act, if in
good faith.

     j.  Relationship to Other  Benefits.  No payment under the Program shall be
taken into  account in  determining  any benefits  under a pension,  retirement,
profit  sharing,  group  insurance  or other  benefit plan of the Company or any
Subsidiary.

     k. Expenses.  The expenses of  administering  the Program shall be borne by
the Company and its Subsidiaries.

     l. Pronouns.  Masculine  pronouns and other words of masculine gender shall
refer to both men and women.

     m. Titles and  Headings.  The titles and  headings  of the  sections in the
Program are for convenience of reference only, and in the event of any conflict,
the text of the Program, rather than such titles or headings, shall control.


10.   Changes in Capital Structure

     Any  agreements  evidencing  Awards shall be subject to  adjustment  by the
Committee as to the number and price of shares of Stock or other  considerations
subject  to such  Awards in the event of  changes  in the  outstanding  Stock by
reason of stock  dividends,  stock splits,  recapitalizations,  reorganizations,
mergers, consolidations,  combinations,  exchanges, or other relevant changes in
capitalization  occurring after the Date of Purchase of any such Awards.  In the
event of any such  change in the  outstanding  Stock,  the  aggregate  number of
shares  available  under the Program and the number of shares  issued  under any
Award shall be  appropriately  adjusted by the  Committee,  whose  determination
shall be conclusive.
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11.   Amendments and Termination

     The Board may at any time amend,  suspend or terminate the Program  subject
to the provisions of this Section 11. No amendment, suspension or termination of
the Program shall, without the consent of the Participant, adversely affect such
Participant's  rights  under the Program in any material  respect.  In addition,
without further stockholder approval, the Board shall not:

     a.  Increase  the maximum  number of shares  which may be issued  under the
Program, except as provided in Section 10;

     b.  Change the  Program to permit a purchase  of Stock at a price less than
Fair Market Value; or

     c. Extend the termination date of the Program.

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