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                                                                    Exhibit 10.3


                      CHEVRON PHILLIPS CHEMICAL COMPANY LP

                     SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN

                                   SECTION I

                                    PURPOSE

The purpose of this Supplemental Executive Retirement Plan ("Supplemental Plan")
is to provide retirement benefits to designated officers and key executives (the
"SERP Members"), of Chevron Phillips Chemical Company LP, (the "Company") and
certain Affiliated Employers (collectively, the "Participating Employers") that
adopt this Supplemental Plan. These benefits are in addition to the retirement
benefits that may be payable under the Chevron Phillips Chemical Company LP
Retirement Plan, (the "Retirement Plan"). To accomplish this, the Participating
Employers intend to make supplemental pension and, if appropriate, survivor
benefit payments, under the terms and conditions described below, to those SERP
Members and to any beneficiaries of SERP Members, whose pension or survivor
benefits payable under the Retirement Plan are reduced by reason of (a) the
limitations imposed under sections 401(a)(17) and/or 415 of the Code, or (b)
their deferral of compensation under the Deferred Compensation Plan (as defined
below).

It is intended that this Supplemental Plan be a plan that is an unfunded
deferred compensation program maintained "for a select group of management or
highly compensated employees" as set forth in the Employee Retirement Income
Security Act of 1974, as amended ("ERISA") Thus, the Plan is subject to Part 1
of Title I of ERISA, but is exempt from Parts 2, 3 and 4 thereof.

                                   SECTION II

                                   DEFINITIONS

In addition to the definitions set forth in Section I, the following words and
phrases shall have the following meanings unless a different meaning is plainly
required by the content.

(a)      "AFFILIATED EMPLOYER" shall have the meaning set forth in the
         Retirement Plan.


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(b)      "BASIC DEATH BENEFIT" shall mean the benefit payable under the
         Retirement Plan to the Beneficiary of a SERP Member on account of the
         death of the SERP Member.

(c)      "BASIC RETIREMENT BENEFIT" shall mean the benefit payable under the
         Retirement Plan to a SERP Member.

(d)      "CODE" shall mean the Internal Revenue Code of 1986, as amended.

(e)      "MEMBER" shall have the meaning set forth in the Retirement Plan.

(f)      "SERP BENEFICIARY" shall mean the person or persons designated by a
         Member, in accordance with the terms of the Retirement Plan, to receive
         any amounts payable under the Retirement Plan after the death of the
         Member.

(g)      "SERP COMMITTEE" shall mean two or more individuals designated by the
         Company to oversee the administration of the Supplemental Plan.

(h)      "SERP MEMBER" shall mean an individual described in Section III of the
         Supplemental Plan, who has satisfied the eligibility requirements under
         the Retirement Plan and has been designated by the Company as being
         eligible to receive benefits hereunder.

(i)      "SUPPLEMENTAL DEATH BENEFIT" shall mean the benefit calculated under
         Section IV of the Supplemental Plan and payable to the SERP
         Beneficiary.

(j)      "SUPPLEMENTAL RETIREMENT BENEFIT" shall mean the benefit calculated
         under Section IV of the Supplemental Plan and payable to a SERP Member.

(k)      "UNRESTRICTED DEATH BENEFIT" shall mean the benefit that would be
         payable under the Retirement Plan to the SERP Beneficiary of a SERP
         Member on account of the death of such SERP Member, calculated: (a)
         without regard to the limitations of sections 401(a)(17) and 415 of the
         Code; and (b) as if amounts deferred by the SERP Member under the
         Deferred Compensation Plan had been paid to the SERP Member in the year
         so deferred.

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(l)      "UNRESTRICTED RETIREMENT BENEFIT" shall mean the benefit that would be
         payable to a SERP Member under the Retirement Plan, calculated: (a)
         without regard to the limitations of sections 401(a)(17), and 415 of
         the Code; and (b) as if amounts deferred by the SERP Member under the
         Deferred Compensation Plan had been paid to the SERP Member in the year
         so deferred.

                                  SECTION III

                                     MEMBERS

No person shall be a Member in this Supplemental Plan unless (a) such individual
is specifically designated as such by the SERP Committee, (b) such individual
has consented to be governed by the terms of this Supplemental Plan by execution
of a written instrument in form satisfactory to the Company, and (c) the
individual is a Member of the Retirement Plan.

A person shall cease to be a Member in this Supplemental Plan in the event of
(a) a Plan amendment having such effect, or (b) the payment of all benefits
payable to the SERP Member under the terms of this Supplemental Plan, or (c) the
person ceasing to be a Member of the Retirement Plan.

                                   SECTION IV

         SUPPLEMENTAL RETIREMENT BENEFITS & SUPPLEMENTAL DEATH BENEFITS

(a)      The Supplemental Retirement Benefit for a SERP Member shall be an
         amount equal to the difference between his or her Basic Retirement
         Benefit and his or her Unrestricted Retirement Benefit. The
         Supplemental Retirement Benefit actually payable to a Participant shall
         be calculated with reference to the Participant's actual Basic
         Retirement Benefit, determined at the time that payments commence under
         the Retirement Plan.

(b)      Each SERP Beneficiary of a SERP Member shall be entitled to a
         Supplemental Death Benefit ar provided as provided in this Section 4(b)
         if the SERP Beneficiary is entitled to the payment of a death benefit
         under the terms of the Retirement Plan. The Supplemental Death


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         Benefit payable to the SERP Beneficiary of a SERP Member shall be an
         amount equal to the difference between the SERP Beneficiary's
         Unrestricted Death Benefit and his or her Basic Death Benefit.

(c)      For purposes of this Supplemental Plan, the determination of any amount
         payable in accordance with the Supplemental Plan shall, except as
         specifically set forth in this Supplemental Plan, be made in the same
         manner as such determination is made under the Retirement Plan
         (including, without limitation, the determination of the "Equivalent
         Actuarial Value" (as defined by the Retirement Plan) of any form of
         benefit payable under the Supplemental Plan).

                                    SECTION V

                            TIME AND FORM OF PAYMENT

(a)      Payments to a SERP Member under the Supplemental Plan shall be made in
         the same manner, for the same period, and on the same basis as payments
         to the SERP Member under the Retirement Plan.

(b)      Notwithstanding the foregoing provisions of this Article V, payment to
         a SERP Member shall be made in a lump sum distribution as soon as
         practicable after his or her termination of employment with the
         Participating Employers and any Affiliated Employer if the present
         value of the SERP Member's Supplemental Retirement Benefit is less than
         $5,000. In determining whether the SERP Member's Supplemental
         Retirement Benefit is less than $5,000, the same provisions set forth
         in the Retirement Plan with respect to the determination of such values
         shall be utilized.

(c)      Payments to a SERP Beneficiary under the Supplemental Plan shall be
         made in the same manner, for the same period, and on the same basis as
         payments to the SERP Beneficiary under the Retirement Plan.
         Notwithstanding the foregoing, payment to a SERP Beneficiary shall be
         made in a lump sum distribution as soon as practicable after the SERP
         Member's death if the present value of such Supplemental Death Benefit
         is not greater than $5,000 (determined in the same manner described
         above).

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                                   SECTION VI

                                SOURCE OF PAYMENT

The benefits payable under this Supplemental Plan to a SERP Member or his or her
SERP Beneficiary shall be paid from the general assets of the Participating
Employer that employed the SERP Member. The SERP Member and his or her SERP
Beneficiary shall be unsecured general creditors of such Participating Employer
with no special or prior right to any assets of the Participating Employer for
payment of any obligations hereunder. Nothing contained in this Supplemental
Plan shall be deemed to create a trust of any kind for the benefit of the SERP
Member or any SERP Beneficiary, or create any fiduciary relationship between the
Participating Employer or the Company and the SERP Member or any SERP
Beneficiary with respect to any assets of the Participating Employer or the
Company.

                                  SECTION VII

                                  WITHHOLDING

Notwithstanding any contrary provision of the Supplemental Plan, all benefits
payable under the Supplemental Plan to a SERP Member or SERP Beneficiary shall
be subject to applicable withholding for federal, state and/or local income tax,
FICA, and any other taxes.

                                  SECTION VIII

                     ADMINISTRATION OF THE SUPPLEMENTAL PLAN

(a)      The SERP Committee shall have the authority to control and manage the
         operation and administration of the Plan. The SERP Committee shall
         serve as such without additional compensation.

(b)      The SERP Committee shall have all discretion and powers necessary to
         supervise the administration of the Plan and to control its operation
         in accordance with its terms, including, but not by way of limitation,
         the following powers:


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         (i)      To interpret the provisions of the Supplemental Plan and to
                  determine, in its sole discretion, any question arising under,
                  or in connection with the administration or operation of, the
                  Supplemental Plan;

         (ii)     To establish and revise accounting methods or formulae for the
                  Supplemental Plan;

         (iii)    To determine the status and rights of SERP Members and SERP
                  Beneficiaries;

         (iv)     To employ such counsel, agents and advisers, and to obtain
                  such legal, clerical and other services, as it may deem
                  necessary or appropriate in carrying out the provisions of the
                  Supplemental Plan;

         (v)      To establish rules for the performance of its powers and
                  duties and for the administration of the Supplemental Plan;

         (vi)     To keep all records and prepare all reports and disclosures
                  necessary to comply with the reporting and disclosure
                  requirements of ERISA and the Code;

         (vii)    To establish a procedure pursuant to which SERP Members and
                  SERP Beneficiaries may Plan, claim Supplemental Plan benefits
                  and appeal denials of such claims; and

         (viii)   To delegate to any one or more persons or entities, severally
                  or jointly, the authority to perform for and on behalf of the
                  SERP Committee one or more of the duties or functions of the
                  SERP Committee under the Supplemental Plan.

(c)      Each decision of a majority of the members of the Supplemental
         Committee then in office shall constitute the final and binding act of
         the Supplemental Committee. The Supplemental Committee may act with or
         without a meeting being called or held and shall keep minutes of all
         meetings held and a record of all actions taken. Except as otherwise
         specifically or generally directed by the Supplemental Committee, any
         action of the Supplemental Committee may be evidenced by a writing
         signed by any member of the



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         Supplemental Committee. All decisions of the Supplemental Committee
         shall be given the maximum deference permitted by law.

                                   SECTION IX

                  RIGHT TO AMEND, MODIFY, SUSPEND OR TERMINATE

The Company may amend, modify, suspend or terminate this Supplemental Plan in
whole or in part, in such manner as it may determine.

(a)      Notwithstanding the foregoing, this Supplemental Plan may not be
         amended, modified, suspended or terminated as to a SERP Member who is
         entitled to receive or has commenced to receive benefits pursuant to
         this Supplemental Plan in a manner which would reduce the benefits
         payable to such individual, without the express written consent of such
         SERP Member or if deceased, such SERP Member's SERP beneficiary.

(b)      No amendment, alteration, modification or termination shall reduce the
         accrued Supplemental Retirement Benefit or Supplemental Death Benefit
         of any SERP Member or SERP Beneficiary; provided, however, that this
         Section IX(b) shall not prevent reductions on account of the SERP
         Member's Basic Retirement Benefit ceasing to be affected (or becoming
         affected to a lesser degree) by the limitations of sections 401(a)(17),
         and/or 415 of the Code, and/or the SERP Members deferrals under the
         Deferred Compensation Plan.

                                   SECTION X

                             CLAIM REVIEW PROCEDURE

Benefits will be provided to each SERP Member or SERP Beneficiary as specified
in this Supplemental Retirement Plan. If such person (a "Claimant") believes
that he has not been provided with the benefits due under this Supplemental
Plan, then he or she may file a request for review with the SERP Committee. The
SERP Committee shall review the claim in accordance with the claims review
procedures set forth in the Retirement Plan. The provisions set forth in the
Retirement Plan concerning the review and appeal of claims (the provisions of
which are

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hereby incorporated by reference) shall be applicable to all claims for benefits
pursuant to this Supplemental Plan.

                                   SECTION XI

                                  MISCELLANEOUS

(a)      No Assignment of Benefits.

         (i)      The benefits provided under the Supplemental Plan may not be
                  alienated, assigned, transferred, pledged or hypothecated by
                  any person, at any time, to any person whatsoever. Except as
                  provided below, these benefits shall be exempt from the claims
                  of creditors or other claimants and from all orders, decrees,
                  levies, garnishment or executions to the fullest extent
                  allowed by law.

         (ii)     Notwithstanding the preceding, benefits payable under the
                  Supplemental Plan shall be paid to the SERP Member, the SERP
                  Member's spouse or the SERP Member's SERP Beneficiary in
                  accordance with the provisions of this Supplemental Plan
                  except to the extent that such benefits are required to be
                  paid to an alternate payee under the provisions of a qualified
                  domestic relations order (a "QDRO") which satisfies the
                  requirements of section 414(p) of the Code. The provisions set
                  forth in the Retirement Plan applicable to QDROs shall apply
                  to the determination of whether any such order satisfies the
                  requirements of section 414(p) of the Code. Further, such
                  QDROs shall be administrated in accordance with the rules set
                  forth in the Retirement Plan, the provisions of which are
                  hereby incorporated by reference; provided, however, a benefit
                  shall be payable to an alternate payee under this Supplemental
                  Plan only at the time payment of the SERP Member's benefit
                  commences under this Supplemental Plan pursuant to Article IV.
                  Neither the Supplemental Plan, the SERP Committee, the
                  Participating Employers nor the Company shall be liable in any
                  manner to any person, including any SERP Member, spouse or
                  SERP Beneficiary, for complying with any such court order or
                  judgment.

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(b)      No Enlargement of Employment Rights. Neither the establishment or
         maintenance of the Supplemental Plan, the payment of any amount by the
         Participating Employers nor any action of the Participating Employers
         or the SERP Committee shall be held or construed to confer upon any
         individual any right to be continued as an employee nor, upon
         dismissal, any right or interest in the Plan other than as provided in
         the Supplemental Plan. The Participating Employers expressly reserve
         the right to discharge any employee at any time.

(c)      Applicable Law; Severability. The Supplemental Plan hereby created
         shall be construed, administered and governed in all respects in
         accordance with the laws of the State of Texas, and, to the extent
         applicable, ERISA and the Code. If any provision of this instrument
         shall be held invalid or unenforceable by a court of competent
         jurisdiction, the remaining provisions hereof shall continue to be
         fully effective.

IN WITNESS WHEREOF, dated this _____ day of __________________, 2001.

                  CHEVRON PHILLIPS CHEMICAL COMPANY LP

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