Exhibit 10.6

                             FIRST AMENDMENT TO THE

                             IMS HEALTH INCORPORATED

                     SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN

                        EFFECTIVE AS OF SEPTEMBER 1, 1999

     1. Section 1.1 of the IMS Health Incorporated Supplemental Executive
Retirement Plan (the "Plan") is hereby amended to read in its entirety as
follows:

          "1.1 "ACTUARIAL EQUIVALENT VALUE" shall mean a benefit of equivalent
               value computed on the basis of the 1983 Group Annuity Mortality
               Table and interest equal to the yield on 30-year Treasury Bonds
               as of the last business day of the Plan Year prior to the year in
               which the relevant calculation occurs; provided, however, that
               for purposes of determining the Actuarial Equivalent Value of the
               amount described in Section 1.23(a) for Members or Vested Former
               Members who participated in the Predecessor to this Plan, the
               foregoing assumptions or the assumptions used in the Predecessor
               to this Plan shall be used, whichever produces the greater
               benefit for the Member or the Vested Former Member."

     2. Section 1.23(b) of the Plan is hereby amended to read in its entirety as
follows:

          "(b) the retirement income payable to a Member or Vested Former Member
          from any `excess benefit plan' as that term is defined in Section
          3(36) of the Employee Retirement Income Security Act of 1974, as
          amended ("ERISA"), any plan described in Section 201(2) of ERISA, and
          any other contract, agreement or other arrangement providing a defined
          pension benefit or defined contribution retirement benefit, in any
          case, maintained or entered into with the Company or an Affiliated
          Employer (excluding this Plan, any Basic Plan, any defined
          contribution plan intended to meet the requirements of Code Section
          401(a) and any elective plan of deferred compensation)."



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     3. Section 1.25 of the Plan is hereby amended to read in its entirety as
follows:

          "1.25 "PREDECESSOR TO THIS PLAN" shall mean the Supplemental Executive
          Benefit Plan of The Dun & Bradstreet Corporation, as amended as of
          December 21, 1994."

     4. Section 1 of the Plan is hereby further amended by adding the following
new Section 1.32 to the end thereof to read in its entirety as follows:

          "1.32 `PLAN ADMINISTRATOR' shall mean the Company, except that any
          action authorized to be taken by the Plan Administrator hereunder may
          also be taken by any committee or person(s) duly authorized by the
          Board or the duly authorized delegees of such duly authorized
          committee or person(s)."

     5. The Plan is hereby further amended by deleting therefrom all references
to the term "Committee" and replacing therefor the term "Plan Administrator."

     6. Section 7.1 of the Plan is hereby amended to read in its entirety as
follows:

          "7.1 AMENDMENT; TERMINATION. The Board of Directors of the Company,
          may, in its sole discretion, terminate, suspend or amend this Plan at
          any time or from time to time, in whole or in part; provided, however,
          that no termination, suspension or amendment of the Plan may adversely
          affect (a) a Member's or Vested Former Member's benefit under the Paln
          to which he or she is entitled hereunder,or, (b) a Vested Former
          Member's right or the right of a Surviving Spouse to receive or to
          continue to receive a benefit in accordance with the Plan, such
          benefits or rights as in effect on the date immediately preceding the
          date of such termination, suspension or amendment. Notwithstanding the
          foregoing, the Employee Benefits Committee of the Company may amend
          the Plan without the approval of the Board of Directors of the Company
          with respect to amendments that such Committee determines do not have
          a significant effect on the cost of the Plan."

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