Exhibit 4(l)


                                 THIRD AMENDMENT
                                         TO
                                 A. SCHULMAN, INC.
                             1991 STOCK INCENTIVE PLAN
                             -------------------------


1.   PURPOSE OF AMENDMENT.

     The purpose of this Amendment to the A. Schulman, Inc. 1991 Stock
Incentive Plan (the "Plan") is to limit the ability of the the Committee
(this term and all other capitalized terms which are not defined herein shall
have the meanings ascribed to such terms in the Plan) to reprice, replace or
grant Options previously granted under the Plan.

2.   AMENDMENT.

     Pursuant to the power reserved by the Board in Section 12.1 of the Plan,
Section 3.2 of the Plan is hereby amended by the addition thereto of the
following as the final sentence thereof:

     "Notwithstanding anything to the contrary set forth above, the Committee
     shall not, without the prior approval of the shareholders of the Company,
     reprice, replace, or regrant any Option previously granted through the
     cancellation and reissuance thereof or by lowering the Option Price
     applicable thereto."

3.   EFFECTIVE DATE.

     The effective date of this Third Amendment shall be December 9, 1999.