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                                                                   EXHIBIT 10.51

                                AMENDMENT 1999-2

                              BECKMAN COULTER, INC.
                        1998 INCENTIVE COMPENSATION PLAN

         WHEREAS, Beckman Coulter, Inc. (the "Company") maintains the Beckman
Coulter, Inc. Incentive Compensation Plan (the "Plan");

         WHEREAS, the Company's Board of Directors has the authority to amend
the Plan; and

         WHEREAS, the Company's Board of Directors has determined that it is in
the best interest of the Company to terminate provisions of the Plan relating to
restricted stock grants to eligible non-employee directors and, in lieu thereof,
to increase the number of stock options granted to such directors.

         NOW, THEREFORE, the Plan is amended, effective as of the date of the
year 2000 annual meeting of stockholders, as follows:

         1.       Section 6.2 is amended to read as follows:

                           "6.2 Annual Option Grants. Subject to adjustments
                  under 6.4, each Eligible Director then continuing in office
                  shall automatically be granted at the close of trading on the
                  day of the annual stockholders meeting in 1999 (without any
                  action by the Administrator) a nonqualified stock option (the
                  grant date of which will be date of such annual stockholder
                  meeting) to purchase 2,000 Common Shares provided, however,
                  that if an Eligible Director takes office other than on the
                  date of an annual stockholders meeting, the Eligible Director
                  shall be granted (without any action by the Administrator) a
                  nonqualified stock option (the grant date of which will be the
                  date he or she participates in the first meeting of the full
                  Board after taking office) to purchase 200 Common Shares, or
                  if greater, the number of Common Shares determined by
                  multiplying 2,000 by (i) the number of days remaining after
                  the grant date until the first anniversary of the preceding
                  annual meeting of the Company's stockholders (provided that
                  such number shall not be greater than 365), divided by (ii)
                  365, then rounded to the next whole number. Beginning with the
                  annual stockholders meeting in the year 2000 and on the date
                  of the annual stockholders meeting each year thereafter for
                  the term of the Plan, the number 2,500 shall be substituted
                  for the number 2,000 each time it appears in the foregoing
                  sentence."

         2.       Section 6.3.1 is amended to read as follows:

                           "6.3.1 Restricted Stock Grants. Immediately following
                  the annual stockholders meeting in 1999, there shall be
                  granted automatically (without any action by the
                  Administrator) a restricted stock award for 100 restricted
                  Common Shares (subject to adjustment under Section 6.4) to
                  each Eligible Director then continuing office. No further
                  restricted stock awards will be granted in any remaining year
                  during the term of this Plan."

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         IN WITNESS WHEREOF, the Company as caused its duly authorized officer
to execute this Amendment to the Plan on November 23, 1999.


                                            BECKMAN COULTER, INC.


                                            By: /s/ Fidencio M. Mares
                                            Its: Vice President, Human Resources