EXHIBIT 10.51


                    FIRST AMENDMENT TO THE WATERS CORPORATION
              1996 NON-EMPLOYEE DIRECTOR DEFERRED COMPENSATION PLAN

                  WHEREAS, Waters Corporation (the "Company") has established
and maintains a deferred compensation plan for the benefit of non-employee
directors of the Company entitled the Waters Corporation 1996 Non-Employee
Director Deferred Compensation Plan (the "Plan").

                  WHEREAS, the Company has paid a stock dividend effective as of
June 10, 1999 ("Stock Dividend"), in the amount of one share of Common Stock for
each share of Common Stock issued and outstanding and held of record as of May
27, 1999, in connection with which Stock Dividend and pursuant to the Plan, the
Company has authorized that the aggregate number of shares of the Common Stock
that may be issued under the Plan be doubled.

                  WHEREAS, as of June 10, 1999, a total of 99,344 shares of the
Company's Common Stock were reserved for issuance pursuant to the Plan, and that
as a result of the Stock Dividend, such number of shares reserved for issuance
was doubled to 198,688 shares.

         NOW, THEREFORE, in accordance with the power of amendment contained in
Section 6 of the Plan, the Company having heretofore taken all necessary action
to amend the Plan, the Plan is hereby amended, as follows:

         1.       The references to "One hundred thousand (100,000)" appearing
                  in each of the first two paragraphs of Section 7 of the Plan
                  are deleted and substituted therefor is the following: "Two
                  hundred thousand (200,000)."

         2.       The words "occurring after June 10, 1999," are to be inserted
                  on the second line of the third paragraph of Section 7, after
                  the words " and the like,".

                  IN WITNESS WHEREOF, the Company has caused this amendment to
be signed on its behalf by its duly authorized representative this 10th day of
June 1999.

                                       WATERS CORPORATION

                                       By:  /s/ BRIAN K. MAZAR
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                                       Its: SENIOR VICE PRESIDENT
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