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                                                                  EXHIBIT 10.2.1

                              AMENDMENT NUMBER 1 TO
                       MEDICAL DIRECTOR SERVICES AGREEMENT

      THIS AMENDMENT NUMBER 1 TO MEDICAL DIRECTOR SERVICES AGREEMENT (this
"Amendment") is made and entered into as of the 1st day of January, 1999, by and
between RCG INDIANA, LLC, a Delaware limited liability company as assignee of
Renal Care Group, Inc. (the "Company"), and INDIANA DIALYSIS MANAGEMENT, P.C.,
an Indiana corporation (the "Group ").

                                   WITNESSETH:

      WHEREAS, Renal Care Group, Inc. and the Group are parties to a Medical
Director Services Agreement (Group Practice/Freestanding Facility), effective as
of February 12, 1996 (the "Agreement"), under which the Group agrees to provide
medical director services for the Company's dialysis facilities located in and
near Ft. Wayne, Indiana, which Agreement was assigned by Renal Care Group, Inc.
to the Company; and

      WHEREAS, the parties to this Amendment now desire to make certain
modifications and amendments to the Agreement as provided herein; and

      WHEREAS, capitalized terms that are used but not defined in this Amendment
that are defined in the Agreement shall have the meanings set forth in the
Agreement;

      NOW, THEREFORE, in consideration of the mutual promises, covenants and
undertakings set forth in this Amendment and in the Agreement, and other good
and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties to this Amendment hereby agree as follows:

      1. Compensation. The parties agree that Section 3.1 of the Agreement is
hereby amended by deleting such section in its entirety and inserting in lieu
thereof, the following:

            3.1 Compensation.

                  (a) In consideration of the services, covenants, and
      agreements agreed to be performed by the Group during the Initial Term and
      any Renewal Term, effective as of February 12, 1999, the Company shall pay
      the Group $500,000 per year, payable in substantially equal monthly
      installments. The parties agree that this medical director fee will be
      fixed for the years ending February 11, 2000, 2001 and 2002. The Group
      agrees to accept the payment under this subsection (a) (as it may be
      adjusted as provided below) as the total compensation for all services,
      covenants and agreements pursuant to this Agreement.

                  (b) (i) Beginning 90 days prior to February 12, 2002 and each
      year thereafter, if either party believes that the fair market value of
      the services provided by the Group under this Agreement has changed in any
      material way since the most recent anniversary of the effective date of a
      change in compensation payable under this Agreement (a "Compensation
      Adjustment Date") (or since February 12, 1999 with respect to the
      Compensation Adjustment Date occurring on February 12, 2002), then such
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      party may notify the other that it believes such a change has occurred and
      the Group and the Company shall negotiate in good faith an adjustment to
      the compensation described in Section 3.1(a) above so that it represents
      fair market value for the duties and responsibilities of the Group to be
      provided during the next year under this Agreement. Notwithstanding the
      foregoing, no adjustment pursuant to this subsection (b)(i) to the
      compensation payable under this Agreement shall be effective unless set
      forth in writing signed by each of the Group and the Company, which
      writing shall be deemed an amendment to this Agreement.

                        (ii) If the Group and the Company are unable to agree on
      an adjustment, then either may require that an adjustment of the
      compensation hereunder be submitted to a qualified independent third party
      mutually selected by both the Group and the Company to determine the fair
      market value of the services required hereunder, the costs and fees of
      which shall be borne equally by the Group and the Company. If the Group
      and the Company are unable to agree on the third party, then each of the
      Company and the Group shall at its own cost and expense select its own
      qualified independent third party and the average of such two
      determinations of fair market value shall be the revised compensation
      unless such determinations are more than 10% apart, in which case such
      third parties shall mutually select an additional qualified independent
      third party, the fees and expenses of which shall be shared equally, who
      shall determine the fair market value of the services hereunder from
      between the range of the amounts determined by the first two appraisals.
      The fair market value of the services as determined in accordance with the
      provisions of this subsection (b)(ii) shall be the compensation payable
      under this Agreement effective as of the applicable anniversary of the
      Compensation Adjustment Date, and such final determination shall be deemed
      an amendment to this Agreement.

                  (c) Any change to the compensation payable hereunder in
      accordance with subsection (b) of this Section 3.1 shall be effective as
      of the applicable anniversary of the Compensation Adjustment Date and
      shall remain effective, and not subject to adjustment under Section 3.1(b)
      or otherwise, for at least 12 months from the effective date of such
      change.

      2. No Further Amendment. Except as expressly modified and amended by this
Amendment, the parties agree that the Agreement shall continue in full force and
effect as provided therein, and the parties reaffirm all of its provisions.

      3. Miscellaneous. The section and other headings used in this Amendment
are for convenience of reference only and shall not affect the interpretation of
this Agreement in any way. This Amendment may be executed in multiple
counterparts, each of which shall be deemed an original for all purposes and all
of which shall be deemed, collectively, one agreement.


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      IN WITNESS WHEREOF, this Amendment is executed effective as of the date
first set forth above.

                               The Company:

                               RCG INDIANA, LLC



                               By:       /s/ R. Dirk Allison
                                  ---------------------------------------
                               Title: Vice President of Manager
                                     ------------------------------------

                               The Group

                               INDIANA DIALYSIS MANAGEMENT, P.C.



                               By:       /s/ Stephen D. McMurray
                                  ---------------------------------------
                               Title:    President
                                     ------------------------------------

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      Each physician executing below acknowledges that he or she has read and
understood the terms of this Amendment and the Agreement amended hereby and
hereby confirms and ratifies the acknowledgement set forth in Section 6.1(i) of
the Agreement and the agreements set forth in Article VII of the Agreement, as
provided therein.

                               /s/ Stephen D. McMurray
                               --------------------------------------
                               STEPHEN D. McMURRAY, M.D.


                               /s/ Robert L. Dettmer
                               --------------------------------------
                               ROBERT L. DETTMER, M.D.


                               /s/ Richard Nelson
                               --------------------------------------
                               RICHARD NELSON, M.D.


                               /s/ John Dyer
                               --------------------------------------
                               JOHN DYER, M.D.

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