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                                                                   Exhibit 4.1

                                 AMENDMENT NO. 2
                                     TO THE
                                RIGHTS AGREEMENT


         This Amendment No. 2, dated as of July 18, 2000 (the "Amendment"), to
the Rights Agreement, dated as of June 15, 1998 (as amended from time to time,
the "Rights Agreement"), between IMS Health Incorporated, a Delaware corporation
(the "Company"), and First Chicago Trust Company, as Rights Agent (the "Rights
Agent").

         WHEREAS, on June 15, 1998, the Company and the Rights Agent entered
into a rights agreement, as amended on March 28, 2000 (the "Original Rights
Agreement");

         WHEREAS, Section 27 of the Original Rights Agreement permits the
Company to amend the Original Rights Agreement in the manner provided herein;

         WHEREAS, Section 27 of the Original Rights Agreement provides that the
Rights Agent shall execute this Amendment upon delivery of a certificate from an
appropriate officer of the Company which states that this Amendment is in
compliance with the terms of Section 27 of the Original Rights Agreement (the
"Officer's Certificate"); and

         WHEREAS, the Officer's Certificate is being delivered to the Rights
Agent concurrently with this Amendment;

         WHEREAS, the Company deems this Amendment to be necessary and desirable
and in the best interests of the holders of Rights and has duly approved this
Amendment;

         WHEREAS, the Company and the Rights Agent wish to amend the Original
Rights Agreement as follows:

         NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, the Company and the Rights Agent
hereby agree as follows:

         1. Section 1(d) is hereby amended and restated in its entirety as
follows:

                  "(d) "Business Day" shall mean any day other than a Saturday,
     a Sunday, or a day on which banking institutions in the State of New
     Jersey, or the State in which the principal office of the Rights Agent
     is located, are authorized or obligated by law or executive order to
     close."

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         2. Section 2 is hereby amended and restated in its entirety as follows:

                  "Section 2. APPOINTMENT OF RIGHTS AGENT. The Company hereby
     appoints the Rights Agent to act as agent for the Company and the
     holders of the Rights (who, in accordance with Section 3 hereof, shall
     prior to the Distribution Date also be the holders of Common Stock) in
     accordance with the terms and conditions hereof, and the Rights Agent
     hereby accepts such appointment. The Company may from time to time
     appoint such co-Rights Agents as it may deem necessary or desirable
     upon ten (10) days prior written notice to the Rights Agent. The Rights
     Agent shall have no duty to supervise and shall in no event be liable
     for the acts or omissions of any such co-Rights Agent."

         3. Section 18(a) is hereby amended and restated in its entirety as
     follows:

                  "(a) The Company agrees to pay to the Rights Agent reasonable
     compensation for all services rendered by it hereunder and, from time
     to time, on demand of the Rights Agent, its reasonable expenses and
     counsel fees and other disbursements incurred in the administration and
     execution of this Agreement and the exercise and performance of its
     duties hereunder. The Company also agrees to indemnify the Rights Agent
     for, and to hold it harmless against, any loss, liability or expense,
     incurred without gross negligence, bad faith or willful misconduct on
     the part of the Rights Agent, for anything done or omitted by the
     Rights Agent in connection with the acceptance and administration of
     this Agreement, including the costs and expenses of defending against
     any claim of liability arising therefrom, directly or indirectly."

         4. Section 20(c) is hereby amended and restated in its entirety as
     follows:

         "(c) The Rights Agent shall be liable hereunder to the Company and any
     other Person only for its own gross negligence, bad faith or willful
     misconduct."

         5. Section 35 is hereby deleted in its entirety.

         6. Except as expressly set forth herein, the Rights Agreement
     shall not by implication or otherwise be supplemented or amended by
     virtue of this Amendment, but shall remain in full force and effect, as
     amended hereby.

         7. This Amendment may be executed in any number of counterparts,
     and each of such counterparts shall for all purposes be deemed to be
     an original, and all such counterparts shall together constitute but
     one and the same instrument.

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         IN WITNESS WHEREOF, the Company and the Rights Agent have executed this
Amendment as of the date and year first written above.


                                 IMS HEALTH INCORPORATED


                                 By:   /s/ Matthew L. Friedman
                                       -------------------------------------
                                       Name:    Matthew L. Friedman
                                       Title:   Vice President - Treasurer


                                 FIRST CHICAGO TRUST COMPANY


                                 By:   /s/ Craig Broomfield
                                       --------------------------------------
                                       Name:    Craig Broomfield
                                       Title:   Senior Account Manager