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                                                                    EXHIBIT 4.1

                                FOURTH AMENDMENT
                                       TO
                               A. SCHULMAN, INC.
                 1992 NON-EMPLOYEE DIRECTORS' STOCK OPTION PLAN

1.  PURPOSE OF AMENDMENT.

    The A. Schulman, Inc. 1992 Non-Employee Directors' Stock Option Plan (the
    "Plan") provides that each Eligible Director (this term and all other
    capitalized terms which are not defined herein shall have the meanings
    ascribed to such terms in the Plan) shall receive an annual grant of options
    to purchase One Thousand (1,000) Shares. The Purpose of this Amendment is to
    increase the number of Shares subject to such annual Option Grants to Two
    Thousand (2,000) Shares and to provide that each Eligible Director shall
    receive an annual grant of Five Hundred (500) Shares of Restricted Stock.

2.  AMENDMENT.

    Pursuant to the power reserved by the Board in Section 10.2 of the Plan, and
    subject to the approval thereof by the stockholders of the Company, the Plan
    is hereby amended as follows:

    A. Section 2 of the Plan is hereby amended by the addition thereto of the
       following Section 2.16:

           "2.16 "Award" means a grant under this Plan of an Option
           or Restricted Stock."

    B.  Section 2 of the Plan further is hereby amended by the addition thereto
       of the following Section 2.17:

           "2.17 "Disability" means a permanent and total disability,
           as determined by the Committee in good faith, upon receipt
           of sufficient competent medical advice from one or more
           individuals, selected by the Committee, who are qualified
           to give professional medical advice."

    C.  Section 2 of the Plan further is amended by the addition thereto of the
       following Section 2.18:

           "2.18 "Restricted Stock" means a grant of Shares pursuant
           to Section 9 herein."

    D. Section 3 of the Plan is hereby amended by (i) the deletion of the phrase
       "optioned or sold" from the first sentence of the first paragraph
       thereof, and the substitution therefor of the word "granted"; (ii) the
       deletion of the word "Options" from the first sentence of the first
       paragraph thereof, and the substitution therefor of the word "Award";
       (iii) the deletion of the phrase "If an Option should expire or become
       unexercisable for any reason without having been exercised in full, the
       unpurchased" from the second paragraph thereof, and the substitution
       therefor of the phrase "If an Award granted under this Plan is cancelled,
       terminates, expires or lapses for any reason, any"; (iv) the deletion of
       the word "thereto" from the second paragraph thereof, and the
       substitution therefor of the phrase "to such Award"; and (v) the deletion
       of the word "Options" from the second paragraph thereof, and the
       substitution therefor of the word "Award".

    E.  Section 4 of the Plan is hereby amended by the deletion of the phrase "a
       grant of an Option" from the end of the first sentence thereof, and the
       substitution therefor of the phrase "an

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       Award". In addition, the word "Option" is hereby deleted from the last
       sentence thereof, and the word "Award" is inserted in its stead.

    F.  Section 5.1 of the Plan is hereby amended by the deletion of the number
       "1,000" therefrom and the substitution therefor of the number "2,000".

    G. Section 5.2 of the Plan is hereby amended by the deletion of the phrase
       "Section 9" therefrom and the substitution therefor of the phrase
       "Section 10".

    H. Section 6 of the Plan is hereby amended and restated in its entirety as
       follows:

           "6. TERM OF PLAN.

                   Subject to approval of the stockholders as
               contemplated by Section 11.1, this Plan shall
               become effective upon its adoption by the Board,
               and shall continue in effect until all Awards
               granted hereunder have expired or been exercised,
               unless sooner terminated under the provisions
               relating thereto. No Award shall be granted after
               ten (10) years from the earlier of the date of the
               adoption of the original Plan or its original
               approval by the stockholders as contemplated by
               Section 11.1."

    I.  Section 7.1 of the Plan is hereby amended by the deletion of the word
       "five" therefrom and the substitution therefor of the phrase "ten (10)".

    J.  Sections 9, 10, 10.1, 10.2, 10.3, 11, 11.1 and 11.2 of the Plan are
       hereby re-numbered as Sections 10, 11, 11.1, 11.2, 11.3, 12, 12.1 and
       12.2, respectively. A new Section 9 of the Plan is hereby added to the
       Plan to read in its entirety as follows:

           "9. RESTRICTED STOCK.

                   9.1 NONDISCRETIONARY ANNUAL GRANT OF
               RESTRICTED STOCK. Each Eligible Director shall
               receive an annual grant of 500 Shares of
               Restricted Stock on each Grant Date subsequent to
               his or her election as a director of the Company.
               The number of Shares subject to annual grant
               hereunder shall be subject to adjustment from time
               to time in accordance with Section 10 hereof.

                   9.2 RESTRICTED STOCK AGREEMENT. Each
               Restricted Stock grant shall be evidenced by a
               Restricted Stock Agreement that shall specify a
               period of restriction (the "Period of
               Restriction"), subject to Section 9.9, terminating
               upon five (5) years after the Grant Date. All
               restrictions shall lapse upon the expiration of
               the Period of Restriction. The Restricted Stock
               Agreement shall include the number of Restricted
               Stock Shares granted and such other provisions as
               the Committee shall determine.

                   9.3 TRANSFERABILITY. Except as provided in
               this Section 9, the Shares of Restricted Stock
               granted herein may not be sold, transferred,
               pledged, assigned, or otherwise alienated or
               hypothecated until the expiration of the Period of
               Restriction. All rights with respect to the
               Restricted Stock granted to an Eligible Director
               under

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               the Plan shall be available during his or her
               lifetime only to such Eligible Director.

                   9.4 OTHER RESTRICTIONS. The Committee shall
               impose such other restrictions on any Shares of
               Restricted Stock granted pursuant to the Plan as
               it may deem advisable including, without
               limitation, restrictions under applicable Federal
               or state securities laws; and may legend the
               certificates representing Restricted Stock to give
               appropriate notice of such restrictions.

                   9.5 CERTIFICATE LEGEND. In addition to any
               legends placed on certificates pursuant to Section
               9.4 herein, each certificate representing Shares
               of Restricted Stock granted pursuant to the Plan
               shall bear the following legend:

                   "The sale or other transfer of the Shares of
               Stock represented by this certificate, whether
               voluntary, involuntary, or by operation of law, is
               subject to certain restrictions on transfer as set
               forth in the A. Schulman, Inc. 1992 Non-Employee
               Directors' Stock Option Plan, as the same has
               heretofore been and may from time to time be
               amended, and in a Restricted Stock Agreement. A
               copy of the Plan and such Restricted Stock
               Agreement may be obtained from the Secretary of A.
               Schulman, Inc."

                   9.6 REMOVAL OF RESTRICTIONS. Except as
               otherwise provided in this Section 9, Shares of
               Restricted Stock covered by each Restricted Stock
               grant made under the Plan shall become freely
               transferable by the Eligible Director after the
               last day of the Period of Restriction. Once the
               Shares are released from the restrictions, the
               Eligible Director shall be entitled to have the
               legend required by Section 9.5 removed from his or
               her Share certificate.

                   9.7. VOTING RIGHTS. During the Period of
               Restriction, Eligible Directors holding Shares of
               Restricted Stock granted hereunder may exercise
               full voting rights with respect to those Shares.

                   9.8. DIVIDENDS AND OTHER DISTRIBUTIONS.

                   (A) The Company shall establish a bookkeeping
               account on behalf of each Eligible Director, for
               the purpose of recording the amount owed to each
               Eligible Director with respect to "dividend
               equivalents" earned during the Period of
               Restriction. For this purpose, "dividend
               equivalent" means an amount equal to each regular
               or special dividend declared with respect to one
               (1) Share of Restricted Stock during the Period of
               Restriction. "Dividend equivalent" shall include
               distributions either in cash or property. Such
               "dividend equivalents" shall be declared and
               credited to the bookkeeping account of each
               Eligible Director simultaneous with the dividend
               payment date for Company stock.

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                   (B) Dividend equivalents shall be subject to
               the same restrictions on transfer as are the
               Shares of Restricted Stock. Amounts credited to
               Eligible Directors' dividend equivalent
               bookkeeping accounts shall not earn interest. The
               Company shall have no obligation to fund the
               amounts set forth in the dividend equivalent
               bookkeeping accounts, and the rights of Eligible
               Directors to these amounts shall be equivalent to
               those of general creditors of the Company.

                   (C) Dividend equivalents shall be paid to
               Eligible Directors in cash, in one lump sum,
               within thirty (30) days following the date the
               restrictions lapse on the Shares of Restricted
               Stock with respect to which such dividend
               equivalents were earned. The decisions of the
               Committee with respect to payout of dividend
               equivalents shall be final and binding on all
               parties and their successors.

                   9.9 TERMINATION OF MEMBERSHIP ON THE BOARD.

                   (A) If an Eligible Director's membership on
               the Board terminates for any reason other than the
               retirement of such Eligible Director upon
               attainment of age 65 or any time thereafter
               ("Retirement"), Disability, death or a Change in
               Control, all Shares of Restricted Stock in respect
               of which the Period of Restriction has not expired
               upon the effective date of termination immediately
               shall be forfeited and returned to the Company
               (and shall once again become available for grant
               under the Plan). The Committee, in its sole
               discretion, shall have the right to provide for
               lapsing of the restrictions on Restricted Stock
               following termination, upon such terms and
               provisions as it deems proper.

                   (B) In the case of an Eligible Director's
               Retirement, Disability, death or upon the
               occurrence of a Change in Control, all
               restrictions on Restricted Stock immediately shall
               lapse, and the Period of Restriction shall expire
               at such time."

    K.  Section 10 of the Plan is hereby amended by deleting the phrase
       "portions thereof" therefrom and substituting therefor the phrase
       "Restricted Stock".

    L.  Section 11.1 of the Plan is hereby amended by the deletion of the word
       "Options" wherever that word appears therein, and the substitution
       therefor of the word "Awards". Section 11.1 further is hereby amended by
       the addition thereto of the words "such Options" after the word "and" and
       before the word "may" in the final sentence thereof.

       Section 11.3 of the Plan is hereby amended by the deletion of the phrase
       "Options already granted" therefrom and the substitution therefor of the
       phrase "outstanding Awards" in the second sentence thereof. Section 11.3
       further is hereby amended by the deletion of the word "Options" in each
       instance where said word appears, and the substitution therefor of the
       word "Awards".

3.  EFFECTIVE DATE.

    The effective date of this Fourth Amendment shall be December 7, 2000,
provided, however, that if this Fourth Amendment is not approved by the
stockholders of the Company at or prior to the Company's 2000 Annual Meeting of
Stockholders, this Fourth Amendment shall be null and void and of no effect
whatsoever.

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