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                                                                     EXHIBIT 2.6

                       AMENDMENT NO. 5 TO THE AMENDED AND
                  RESTATED OPERATIONS AND SETTLEMENT AGREEMENT


         This Amendment No. 5 ("Amendment") to the Amended and Restated
Operations and Settlement Agreement (the "Agreement") is entered into as of
November 30, 1999, among the Commissioner of the Department of Corporations of
the State of California (the "Commissioner" acting for himself and the
Department of Corporations of the State of California (collectively, the
"State")), J. Mark Abernathy, as Special Monitor-Examiner, Caremark Rx, Inc.,
f/k/a/ MedPartners, Inc., a Delaware corporation, and its successors and
assigns ("MedPartners") and MedPartners Provider Network, Inc., a California
corporation ("MPN"), as a debtor and debtor in possession in the Bankruptcy
Case. Capitalized terms not otherwise defined herein shall have the meanings
ascribed to them in the Agreement.

                                    RECITALS

         WHEREAS, the parties entered into the Agreement as of June 16, 1999;

         WHEREAS, the parties entered into Amendment No. 1 to the Agreement as
of July 31, 1999;

         WHEREAS, the parties entered into Amendment No. 2 to the Agreement as
of August 31, 1999;

         WHEREAS, the parties entered into Amendment No. 3 to the Agreement as
of September 30, 1999;

         WHEREAS, the parties entered into Amendment No. 4 to the Agreement as
of October 31, 1999; and

         WHEREAS, the parties desire to allow for additional time for
implementation of the Agreement to be effected.

         NOW THEREFORE, in consideration of the mutual covenant and agreements
contained herein and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties agree as follows:

                                   AGREEMENT

         1.     Section 13.2 of the Agreement is amended by deleting "November
30, 1999" and inserting in its place "December 31, 1999".

         2.     The second sentence of Section 3.8(b) of the Agreement is
amended by deleting "November 30, 1999" and inserting in its place "December
15, 1999."

         3.     The Agreement shall remain unchanged in all other respects.

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         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed as of the date first above written.


                              CAREMARK RX, INC.
                              a Delaware corporation

                              By:      /s/ Edward L. Hardin, Jr.
                                 ----------------------------------------------
                              Title:  Executive Vice President
                                      -----------------------------------------

                              MEDPARTNERS PROVIDER NETWORK, INC.,
                              a California corporation

                              By       /s/ Don Garner
                                 -----------------------------------------------
                              Title:  Secretary
                                      ------------------------------------------

                              COMMISSIONER OF THE DEPARTMENT OF
                              CORPORATIONS

                              By  /s/ William Kenefick
                                 -----------------------------------------------
                                      William Kenefick

                              Title: Acting Commissioner of the Department of
                                     Corporations


                              J. MARK ABERNATHY,
                              as Special Monitor-Examiner and not individually

                              By      /s/  J. Mark Abernathy
                                 -----------------------------------------------
                              Title: J. Mark Abernathy,
                                     as Special Monitor-Examiner


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