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                                                                   Exhibit 10.18

                                                      Board of Directors Amended
                                                                February 9, 1998

                      NON-EMPLOYEE DIRECTOR RETIREMENT PLAN
                          OF PHILLIPS PETROLEUM COMPANY

                               ARTICLE I - PURPOSE

The Non-Employee Director Retirement Plan is intended to provide Non-Employee
Directors with income commencing upon their retirement from service on the
Phillips Petroleum Company Board of Directors.

                            ARTICLE II - DEFINITIONS

The following terms, when used in this Plan, have the following meaning unless
the context clearly indicates otherwise:

      1.    "Annual Board Service Retainer" shall mean the sum of the cash
            compensation paid for Board service exclusive of compensation for
            committee membership and of fees for attendance at Board or
            Committee meetings, if any, plus the value of the Company common
            stock granted, if any, to a Non-Employee Director during the twelve
            calendar months immediately preceding the date on which the Non-
            Employee Director retires, such value to be determined as the
            product of the number of shares of such common stock granted
            multiplied by the higher of the Fair Market Value for the last year
            or the average of the

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            high three Fair Market Values calculated in accordance with Article
            II, Section 6, for the last ten years preceding the Non-Employee
            Director's retirement.

      2.    "Board" shall mean the Board of Directors of the Company.

      3.    "Chief Executive Officer" shall mean the Chief Executive Officer of
            the Company.

      4.    "Company" shall mean Phillips Petroleum Company.

      5.    "Disability" shall mean that condition in which, by reason of bodily
            injury or disease, a Non-Employee Director is prevented from serving
            in such capacity. All determinations of Disability shall be made by
            a physician selected by the Company.

      6.    "Fair Market Value" shall be calculated as the average of the high
            three monthly fair market values of the Company common stock during
            the twelve calendar months preceding the month in which the
            Non-Employee Director retires. The monthly fair market value of the
            Company common stock is the average of the daily fair market value
            of the stock for each trading day of the month. The daily fair
            market value of the stock shall be deemed equal to the average of
            the high and low selling prices


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            of the stock on the New York Stock Exchange, as reported in the Wall
            Street Journal.

      7.    "Non-Employee Director" shall mean a member of the Board of
            Directors who is not a present employee nor former employee of the
            Company or any of its subsidiaries.

      8.    "Normal Retirement Date" shall mean the date of the Annual
            Stockholders Meeting of the Company in the year in which the
            director is no longer eligible for election as a director as defined
            in the Bylaws of the Company, currently the year in which the
            director attains age 71.

      9.    "Plan" shall mean the Non-Employee Director Retirement Plan of
            Phillips Petroleum Company, the terms and provisions of which are
            herein set forth, together with such amendments thereto as may
            hereafter from time to time be adopted.

      10.   "Retires" or "Retirement" shall mean the termination of Board
            service due to a) the Non-Employee Director's not being nominated
            for election to the Board; or b) the Non-Employee Director's not
            being reelected to Board service after being so nominated; or c) the
            Non-Employee Director's resignation from Board service as a result
            of the Director's Disability or any reason, acceptable to a majority
            of the remaining members of the Board of


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            Directors.

      11.   "Years of Service" shall mean the number of full and partial
            consecutive calendar years during which the Non-Employee Director
            was a member of the Board; provided, however that only a
            Non-Employee Director whose Normal Retirement Date occurs in 1998,
            shall accrue Years of Service after December 31, 1997, and further
            that no Non-Employee Director shall accrue Years of Service after
            the date of the 1998 Annual Stockholders Meeting of the Company.

                            ARTICLE III - ELIGIBILITY

Only Non-Employee Directors are eligible to participate in the Plan.

                   ARTICLE IV - PAYMENT OF RETIREMENT BENEFITS

Upon Retirement from Board service each Non-Employee Director shall receive
payments under this Plan. Notwithstanding anything to the contrary in this Plan,
no payments shall be made under this Plan for any Non-Employee Director who has
given written consent to the Company to receive an Award of Restricted Stock, as
of March 2, 1998, under the Phillips Petroleum Company Stock Plan for
Non-Employee Directors representing and in lieu of his or her accrued benefits
under this Plan.


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      a)    These payments shall be made on a monthly basis beginning on or
            about the first of the month after Retirement. The amount of these
            monthly payments shall be equal to the Annual Board Service Retainer
            divided by 12; provided, however, that the amount of payments to any
            retired Non-Employee Director who has commenced receiving payments
            from this Plan prior to April 10, 1995, shall not be increased or
            paid in a different manner, but shall be paid in the same amount and
            manner as in effect at the time payments commenced. These payments
            shall continue for a number of months equal to Years of Service
            times 12.

      b)    Notwithstanding (a) above, a Retiring Non-Employee Director may, not
            earlier than 150 days nor later than 30 days prior to the date
            retirement benefit payments would begin, express a preference, in
            the manner prescribed by the Chief Executive Officer, to have the
            monthly payment provided hereunder converted to one lump sum payment
            which is calculated as the present value of the monthly payment
            amount using the December 1 of the year prior to Retirement rate of
            the 30-year Treasury Bond as quoted in the Federal Reserve
            Statistical Release Bulletin No. H.15, or the comparable successor
            publication, and the number of Years of Service.

            All or part of such lump sum payment may be either paid


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            to the Non-Employee Director or considered for deferral under the
            Deferred Compensation Plan for Non-Employee Directors of Phillips
            Petroleum Company. The Chief Executive Officer shall consider such
            indication of preference for a lump sum and shall respectively
            decide in the Chief Executive Officer's sole discretion whether to
            accept or reject the preference expressed. In the event the Chief
            Executive Officer accepts such Non-Employee Director's preference
            for a lump sum, part or all of the retirement benefit shall be paid
            in a lump sum as soon as practicable after the later of such
            acceptance or on or about the first of the month after Retirement.

                   ARTICLE V - DEATH OF NON-EMPLOYEE DIRECTOR

In the event a Non-Employee Director dies prior to Retirement, no benefits shall
be payable from this Plan. After commencement of Retirement payments, if paid as
a monthly payment determined in accordance with Article IV (a), such monthly
payments will continue until the total number of payments has been made, or the
death of the retired Non-Employee Director, whichever occurs first. If death
occurs first, then the remaining payments shall be made to the surviving spouse,
if any. If there is no surviving spouse, or if the surviving spouse should die,
then there will be no further payment obligation under this Plan.


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                           ARTICLE VI - ADMINISTRATION

The Chief Executive Officer is authorized, subject to the provisions of the
Plan, to establish rules and regulations, to make determinations under and such
interpretations of, and to take steps in connection with the Plan as the Chief
Executive Officer deems necessary or advisable, and to appoint agents as the
Chief Executive Officer deems appropriate for the proper administration of the
Plan. Each determination, interpretation, or other action made or taken pursuant
to the provisions of the Plan by the Chief Executive Officer shall be reported
to the Board of Directors and once so reported shall be final and shall be
binding and conclusive for all purposes and upon all persons.

               ARTICLE VII - TERMINATION OR AMENDMENT OF THE PLAN

The Board may at any time terminate the Plan and may from time to time alter or
amend the Plan, or any part thereof, (including any amendment deemed necessary
to ensure that the Company may comply with any regulatory requirement);
provided, however, that no director may act to terminate or amend the Plan if
such action would either increase benefits payable under the Plan to that
director or remove or reduce the risk that such director's benefits under the
Plan might be forfeited. Such termination or amendment will not negatively
impact any rights or benefits accrued to date of such termination or amendment
under this Plan. After the 1998 Annual Stockholders Meeting of the Company and


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upon the final payment of all amounts owed to Retired Non-Employee Directors and
their surviving spouses, this Plan shall automatically terminate without further
action of this Board.


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                        ARTICLE VIII - NON-ASSIGNABILITY

Retirement payments may not be pledged, anticipated, assigned (either at law or
in equity), alienated or subject to attachment, garnishment, levy, execution or
other legal or equitable process.

                           ARTICLE IX - MISCELLANEOUS

(a)   All amounts payable under this Plan are unfunded and unsecured benefits
      and shall be paid solely from the general assets of the Company and any
      rights accruing to the Non-Employee Director or the surviving spouse under
      the Plan shall be those of a unsecured general creditor; provided,
      however, that the Company may establish a grantor trust to pay part or all
      of its Plan payment obligations so long as the Plan remains unfunded for
      federal tax purposes.

(b)   Except as otherwise provided herein, the Plan shall be binding upon the
      Company, its successors and assigns, including but not limited to any
      corporation which may acquire all or substantially all of the Company's
      assets and business or with or into which the Company may be consolidated
      or merged.

(c)   This Plan shall be construed, regulated, and administered in accordance
      with the laws of the State of Delaware except to the extent that said laws
      have been preempted by the laws of


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            the United States.

                     ARTICLE X - EFFECTIVE DATE OF THE PLAN

The Plan is amended and restated effective as of January 1, 1998.


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