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                                                                   EXHIBIT 10.56

                               THIRD AMENDMENT TO
                    FIRST AMENDED AND RESTATED LOAN AGREEMENT

         This Third Amendment to First Amended and Restated Loan Agreement
("Amendment") is entered into as of the 29th day of September, 2000 by and among
RENAL CARE GROUP, INC. ("Borrower"), a Delaware corporation; AMSOUTH BANK
("AmSouth"), an Alabama banking association, as an initial party to the
documents described below and as successor by merger to First American National
Bank, a national banking corporation, FIRST UNION NATIONAL BANK ("FUNB"), a
national banking association, BANK OF AMERICA, N.A. ("Bank of America"), a
national banking association, SUNTRUST BANK ("SunTrust"), a Georgia banking
corporation and successor in interest to SunTrust Bank, N.A., a national banking
association, and WELLS FARGO BANK ARIZONA, N.A. ("Wells Fargo"), a national
banking association and successor by merger to Norwest Bank Arizona, N.A., a
national banking association (AmSouth, FUNB, Bank of America, SunTrust and Wells
Fargo are referred to collectively as the "Lenders"); and Bank of America, in
its capacity as Agent for the Lenders ("Agent").

                                R E C I T A L S:

         WHEREAS, the Lenders (for their own accounts or through their
predecessors in interest), Agent and Borrower have previously entered into that
First Amended and Restated Loan Agreement dated as of August 4, 1997, as amended
by that First Amendment to First Amended and Restated Loan Agreement dated as of
October 7, 1997, and as further amended by that Second Amendment to First
Amended and Restated Loan Agreement dated as of June 23, 1999 (as amended, the
"Loan Agreement"); and

         WHEREAS, the parties wish to further amend the Loan Agreement in
certain respects ;

         NOW, THEREFORE, for valuable consideration, the receipt and sufficiency
of which are acknowledged, the parties agree as follows:

         1.       The definition of "Consolidated EBITDA" in Article I of the
Loan Agreement is hereby amended to read in full as follows:

         "CONSOLIDATED EBITDA" means (i) the net income of Borrower and all
         other Borrower Entities, plus the amount of expenses for interest,
         income taxes, depreciation and amortization, for the four most recent
         fiscal quarters preceding a date of determination, calculated on a
         consolidated basis according to GAAP before extraordinary items, and
         calculated on a pro forma basis to give effect to Acquisitions that
         occurred within the period over which Consolidated EBITDA is being
         determined, with such pro forma calculation to be accomplished pursuant
         to operating and financial assumptions customary in such circumstances
         as Agent may approve, (ii) plus any noncash and nonrecurring charges,
         (iii) plus the amount of the deduction from income taken to reflect


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         income attributed to minority interests, and (iv) less the amount, if
         any, by which the contribution to Consolidated EBITDA by
         Nonparticipating Subsidiaries and Permitted Equity Investments in the
         aggregate would exceed fifteen percent (15%) of Consolidated EBITDA.

         2.       Subsection (f) of the definition of "Permitted Acquisition" in
Article I of the Loan Agreement is hereby amended to revise the two occurrences
of the words and figures "ten percent (10%)" therein to read "fifteen percent
(15%)".

         3.       Section 6.20 of the Loan Agreement is hereby amended to read
in full as follows:

         6.20 Distributions. Except in favor of other Borrower Entities, no
         Borrower Entity shall declare or pay any dividends, member
         distributions or other payments on account of its equity interests.
         Borrower Entities may repurchase their own stock or any warrants,
         options or other rights with respect thereto, even if the repurchase
         would be construed as a distribution for corporate law purposes,
         provided that after giving effect to any repurchase, Borrower shall be
         in compliance with all financial covenants and other requirements under
         this Agreement, including, but not limited to, the Consolidated Net
         Worth requirement set forth in Section 7.1 hereof.

         4.       Section 7.2 of the Loan Agreement is hereby revised to read in
 full as follows:

                  7.2      Leverage Ratio.  Borrower shall maintain a Leverage
                  Ratio, measured as of the end of each fiscal quarter for the
                  previous four consecutive fiscal quarters, of no greater than
                  2.50:1.00.

         5.       Borrower warrants and represents that (a) the Loan Documents
are valid, binding and enforceable against Borrower according to their terms,
subject to principles of equity and laws applicable to the rights of creditors
generally, including bankruptcy laws, and (b) no Unmatured Default or Event of
Default presently exists under the Loan Documents. Borrower acknowledges that,
to the best of Borrower"s knowledge, information and belief, Borrower"s
obligations evidenced by the Loan Documents are not subject to any counterclaim,
defense or right of setoff, and Borrower hereby releases Agent and Lenders from
any claim of which Borrower is aware as of the execution of this Amendment.

         6.       As amended hereby, the Loan Agreement remains in full effect,
and all agreements among the parties with respect to the subject hereof are
represented fully in this Amendment and the other written documents among the
parties. The validity, construction and enforcement hereof shall be determined
according to the substantive laws of the State of Tennessee, and all matters of
venue, dispute resolution and other general matters respecting this Amendment
shall be governed by the provisions of the Loan Agreement.


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         7.       Borrower shall pay all reasonable expenses of Agent, including
attorneys" fees, incurred in the preparation and negotiation of this Agreement.

         8.       As a condition to the effectiveness of this Amendment,
Borrower shall pay to Agent for the Pro Rata account of Lenders an amendment fee
in the total amount of Two Hundred Seventy-five Thousand and No/100 dollars
($275,000.00).

         9.       This Amendment may be executed in counterparts, each of which
shall constitute an original hereof. This Amendment shall be effective, subject
to the conditions stated herein, upon the parties" exchange by telecopier of
copies hereof showing the signatures of the other parties; provided, however,
each party shall immediately forward an executed original hereof to Agent. The
failure of any party to so provide Agent with an original hereof shall not
impair the validity of this Amendment, but shall entitle Agent to obtain
specific performance of the obligation to provide an executed original of this
Amendment.

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      Executed as of the date first written above.

                    RENAL CARE GROUP, INC.,
                    a Delaware corporation, as Borrower

                    By: /s/ R. Dirk Allison
                       ---------------------------------------------------------
                           R. Dirk Allison, Chief Financial Officer

                    BANK OF AMERICA, N.A., a national banking
                    association, as a Lender, Swingline Lender and Agent

                    By: /s/ Sandra G. Hamrick
                       ---------------------------------------------------------
                            Sandra G. Hamrick, Senior Vice President

                    AMSOUTH BANK,
                    an Alabama banking corporation, as a Lender

                    By: /s/ Buzz Carter
                       ---------------------------------------------------------
                            Buzz Carter, Vice President

                    FIRST UNION NATIONAL BANK,
                    a national banking association, as a Lender and Co-Agent

                    By: /s/ Keith Law
                       ---------------------------------------------------------
                            Keith Law, Senior Vice President

                    WELLS FARGO BANK ARIZONA, N.A.,
                    a national banking association, as a Lender


                    By: /s/ Carolyn L. Ashby
                       ---------------------------------------------------------
                            Carolyn L. Ashby, Vice President

                    SUNTRUST BANK, a Georgia banking corporation,
                    as a Lender and Co-Agent


                    By: /s/ Mark D. Mattson
                       ---------------------------------------------------------
                            Mark D. Mattson, Vice President



              [Signature Page to Second Amendment to Third Amended
                          and Restated Loan Agreement]


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