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                                                                   EXHIBIT 10.13

                                                                  EXECUTION COPY

                                                                       EXHIBIT A

                                FOURTH AMENDMENT

     FOURTH AMENDMENT, dated as of September 13, 2001 (this "FOURTH AMENDMENT"),
representing an amendment to the Amended and Restated Credit Agreement, dated as
of March 26, 1999 (as amended, supplemented or otherwise modified, the "CREDIT
AGREEMENT"), among CHS/COMMUNITY HEALTH SYSTEMS, INC., a Delaware corporation
and formerly known as Community Health Systems, Inc. (the "BORROWER"), COMMUNITY
HEALTH SYSTEMS, INC., a Delaware corporation and formerly known as Community
Health Systems Holdings Corp. ("HOLDCO"), the several lenders from time to time
parties thereto (the "LENDERS"), THE CHASE MANHATTAN BANK, as administrative
agent for the Lenders (in such capacity, the "ADMINISTRATIVE AGENT") and BANK OF
AMERICA, N.A. and THE BANK OF NOVA SCOTIA, as the co-agents for the Lenders
(collectively, the "CO-AGENTS").


                              W I T N E S S E T H :
                              - - - - - - - - - -

     WHEREAS, the Borrower, HoldCo, the Administrative Agent, the Co-Agents and
the Lenders are parties to the Credit Agreement;

     WHEREAS, the Borrower and HoldCo have requested that the Administrative
Agent and the Required Lenders agree to amend certain provisions of the Credit
Agreement; and

     WHEREAS, the Administrative Agent and the Lenders parties hereto are
willing to agree to the requested amendments, but only upon the terms and
conditions set forth herein;

     NOW, THEREFORE, for valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, and in consideration of the premises contained
herein, the parties hereto agree as follows:

     1. DEFINED TERMS. Unless otherwise defined herein, capitalized terms which
are defined in the Credit Agreement are used herein as defined therein.

     2. AMENDMENT TO SUBSECTION 1.1 (DEFINED TERMS). Subsection 1.1 of the
Credit Agreement is hereby amended by adding alphabetically therein the
following definitions:

               "CONVERTIBLE SUBORDINATED DEBT": as defined in subsection 13.2(h)
          of the Credit Agreement.

               "FOURTH AMENDMENT": the Fourth Amendment dated as of September
          13, 2001 to the Credit Agreement.

               "FOURTH AMENDMENT EFFECTIVE DATE": as defined in Section 7 of the
          Fourth Amendment.

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               "HIGH YIELD SUBORDINATED DEBT": as defined in Section 3 of the
          Fourth Amendment.

     3. AMENDMENT TO SUBSECTION 13.2 (INDEBTEDNESS). Subsection 13.2 of the
Credit Agreement is hereby amended by:

               (a) deleting paragraph (c) of such subsection in its entirety and
          substituting, in lieu thereof, the following:

                    (c) Indebtedness of the Company evidenced by the
               Subordinated Note in an aggregate principal amount at any one
               time outstanding of up to the aggregate principal amount of the
               Subordinated HoldCo Debentures and the Convertible Subordinated
               Debt; and

               (b) deleting paragraph (h) of such subsection in its entirety and
          substituting, in lieu thereof, the following:

                    (h)(i) Indebtedness of HoldCo evidenced by the Subordinated
               HoldCo Debentures, (ii) any subordinated debt issuance by HoldCo
               that is convertible at the option of the holder or issuer thereof
               into common stock of HoldCo (any such subordinated debt,
               "CONVERTIBLE SUBORDINATED DEBT") or (iii) any other subordinated
               debt issued by HoldCo ("HIGH YIELD SUBORDINATED DEBT"), provided
               that (A) the aggregate principal amount of the Subordinated
               HoldCo Debentures, the Convertible Subordinated Debt and the High
               Yield Subordinated Debt at any one time outstanding shall not
               exceed $500,000,000, (B) no payments of principal on account of
               any such Convertible Subordinated Debt or High Yield Subordinated
               Debt are scheduled to be payable prior to June 30, 2006, (C) the
               weighted average of the interest rates on any such outstanding
               Convertible Subordinated Debt or High Yield Subordinated Debt
               shall not be higher than the interest rate on the Subordinated
               HoldCo Debentures and (D) the terms and provisions of any such
               Convertible Subordinated Debt or High Yield Subordinated Debt
               relating to subordination shall be consistent with market terms
               for comparable debt issues;

     4. AMENDMENT TO SUBSECTION 13.12 (SUBORDINATED NOTE; SUBORDINATED HOLDCO
DEBENTURES; HIGH YIELD SUBORDINATED DEBT). Subsection 13.12 of the Credit
Agreement is hereby amended by deleting such subsection in its entirety and
substituting, in lieu thereof, the following:

          13.12 SUBORDINATED NOTE; SUBORDINATED HOLDCO DEBENTURES; CONVERTIBLE
     SUBORDINATED DEBT. (a)(i) Make any payment in violation of any of the
     subordination provisions of the Subordinated Note; or (ii) waive or
     otherwise relinquish any of its rights or causes of action arising under or
     arising out of the terms of the Subordinated Note or consent to any
     amendment, modification or supplement to the terms of the Subordinated Note
     in each case under this clause (ii) in any material respect or in any
     respect adverse to the Lenders, except (x) that the interest rate thereon
     may be adjusted at such time to correspond to the then weighted average of
     the interest rates on any Convertible Subordinated Debt, Subordinated
     HoldCo Debentures and High Yield Subordinated Debt

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     then outstanding, (y) with the consent of the Required Lenders and (z) that
     HoldCo may contribute all or any portion of the principal amount of the
     Subordinated Note to the capital of the Company; PROVIDED that promptly
     following any contribution of all or any portion of the principal amount of
     the Subordinated Note, all or such portion, as the case may be, of the
     Subordinated Note is canceled; or (iii) make any optional payment or
     prepayment on or redeem or otherwise acquire, purchase or defease the
     Subordinated Note; PROVIDED that the Company may optionally prepay, redeem
     or acquire the Subordinated Note with the proceeds of issuances in
     registered public offerings of shares of common stock of HoldCo after the
     Fourth Amendment Effective Date, so long as the aggregate amount of all
     such prepayments, redemptions and acquisitions shall not exceed all such
     common stock proceeds received during such period after the Fourth
     Amendment Effective Date.

          (b)(i) Make any payment in violation of any of the subordination
     provisions of the Subordinated HoldCo Debentures, the Convertible
     Subordinated Debt or the High Yield Subordinated Debt; or (ii) waive or
     otherwise relinquish any of its rights or causes of action arising under or
     arising out of the terms of the Subordinated HoldCo Debentures, the
     Convertible Subordinated Debt or the High Yield Subordinated Debt or
     consent to any amendment, modification or supplement to the terms of the
     Subordinated HoldCo Debentures, the Convertible Subordinated Debt or the
     High Yield Subordinated Debt except with the consent of the Required
     Lenders; or (iii) make any optional payment or prepayment on or redeem or
     otherwise acquire, purchase or defease the Subordinated HoldCo Debentures,
     the Convertible Subordinated Debt or the High Yield Subordinated Debt;
     PROVIDED that HoldCo may optionally prepay, redeem or acquire the
     Subordinated HoldCo Debentures or the Convertible Subordinated Debt (A)
     with the proceeds of (I) any and all prepayments, redemptions and
     acquisitions of the Subordinated Note by the Company pursuant to clause
     (a)(iii) above, (II) issuances of any Convertible Subordinated Debt or, in
     the case of any Convertible Subordinated Debt, issuances of any High Yield
     Subordinated Debt or (III) any public offering of shares of common stock of
     HoldCo net of any fees or expenses (including underwriting commissions)
     incurred in connection with the issuance thereof, or (B) in exchange for
     shares of common stock of HoldCo.

     5. AMENDMENT TO SECTION 14 (EVENTS OF DEFAULT). Section 14 of the Credit
Agreement is hereby amended by deleting:

          (a) paragraph (k) of such section in its entirety and substituting, in
     lieu thereof, the following:

               (k) HoldCo shall cease to own, directly or indirectly, 100% of
          the issued and outstanding capital stock of the Company, free and
          clear of all Liens (other than the Lien granted pursuant to the HoldCo
          Pledge Agreement), or HoldCo shall conduct, transact or otherwise
          engage in any business or operations, incur, create, assume or suffer
          to exist any Indebtedness, Contingent Obligations or other liabilities
          or obligations or Liens (other than pursuant to any of the Credit
          Documents), or own, lease, manage or otherwise operate any properties
          or assets, other than (1) incident to the ownership of the Pledged
          Stock and the Pledged Note (as such terms are defined in the HoldCo
          Pledge Agreement),

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          (2) as permitted by this Agreement, (3) incident to the ownership of
          capital stock or other equity interests in any person to the extent
          (i) the acquisition thereof by the Company would constitute a
          Permitted Acquisition and (ii) such capital stock or equity interests
          are contributed to the Company promptly following HoldCo's acquisition
          thereof and (4) the making of the Subordinated Loan or the issuance of
          the Subordinated HoldCo Debentures, any Convertible Subordinated Debt
          or any High Yield Subordinated Debt and (5) to the extent necessary to
          effect the IPO and subsequent offerings or issuances of shares of
          common stock of HoldCo and other transactions customarily incident
          thereto; or

          (b) paragraph (l) of such section in its entirety and substituting, in
     lieu thereof, the following:

               (l) FL Affiliates shall cease to own at least 25% of the
          outstanding capital stock of HoldCo, free and clear of all Liens; or,
          any person or group (other than the FL Affiliates) acquires beneficial
          ownership (within the meaning of Rule 13d-3 of the Securities and
          Exchange Commission promulgated under the Securities Exchange Act of
          1934, as amended) of a percentage of the outstanding capital stock of
          HoldCo greater than that percentage owned beneficially by the FL
          Affiliates; or, any person or group (other than the FL Affiliates)
          shall at any time have the right to designate or elect a majority of
          the Board of Directors of HoldCo; or, if a Change of Control as
          defined in the indenture governing any Convertible Subordinated Debt
          or High Yield Subordinated Debt shall occur.

     6. AMENDMENT TO SECTION 10 OF THE HOLDCO GUARANTEE. Section 10 of the
HoldCo Guarantee is hereby amended by deleting such section in its entirety and
substituting, in lieu thereof, the following:

          10. COVENANT. The Guarantor agrees that it will not engage in or
     conduct, transact or otherwise engage in any business or operations, or
     incur, create, assume or suffer to exist any Indebtedness, Contingent
     Obligations or other liabilities or obligations or Liens, or own, lease,
     manage or otherwise operate any properties or assets, other than (i)
     incident to the ownership of the capital stock of the Company and the
     Subordinated Note, (ii) as permitted by the Credit Agreement, (iii)
     incident to the ownership of capital stock or other equity interests in any
     Person to the extent (x) the acquisition thereof by the Company would
     constitute a Permitted Acquisition and (y) such capital stock or equity
     interests are contributed to the Company promptly following the Guarantor's
     acquisition thereof, (iv) the making of the Subordinated Loan and the
     issuance of the Subordinated HoldCo Debentures or Convertible Subordinated
     Debt and the use of the proceeds therefrom as expressly contemplated in the
     Credit Agreement and (v) to the extent necessary to effect the IPO and
     subsequent offerings or issuances of shares of common stock of HoldCo or
     any Convertible Subordinated Debt or any High Yield Subordinated Debt and
     other transactions customarily incident thereto.

     7. CONDITIONS TO EFFECTIVENESS OF THIS FOURTH AMENDMENT. This Fourth
Amendment shall become effective upon receipt by the Administrative Agent of
counterparts of this Fourth Amendment duly executed by each of the Borrower,
HoldCo and the Administrative

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Agent and consented to by the Required Lenders (such date, the "FOURTH AMENDMENT
EFFECTIVE DATE").

     8. REPRESENTATIONS AND WARRANTIES. On and as of the date hereof and after
giving effect to this Fourth Amendment, the Borrower hereby confirms, reaffirms
and restates the representations and warranties set forth in Section 10 of the
Credit Agreement MUTATIS MUTANDIS, except to the extent that such
representations and warranties expressly relate to a specific earlier date in
which case the Borrower hereby confirms, reaffirms and restates such
representations and warranties as of such earlier date, PROVIDED that the
references to the Credit Agreement in such representations and warranties shall
be deemed to refer to the Credit Agreement as amended pursuant to this
Amendment.

     9. CONTINUING EFFECT; NO OTHER AMENDMENTS. Except as expressly set forth in
this Fourth Amendment, all of the terms and provisions of the Credit Agreement
are and shall remain in full force and effect and the Borrower shall continue to
be bound by all of such terms and provisions. The amendments provided for herein
are limited to the specific subsections of the Credit Agreement specified herein
and shall not constitute an amendment of, or an indication of the Administrative
Agent's or the Lenders' willingness to amend or waive, any other provisions of
the Credit Agreement or the same subsections for any other date or purpose.

     10. EXPENSES. The Borrower agrees to pay and reimburse the Administrative
Agent for all its reasonable costs and expenses incurred in connection with the
preparation and delivery of this Fourth Amendment, including, without
limitation, the reasonable fees and disbursements of counsel to the
Administrative Agent.

     11. COUNTERPARTS. This Fourth Amendment may be executed by one or more of
the parties to this Fourth Amendment on any number of separate counterparts
(including by telecopy), and all of said counterparts taken together shall be
deemed to constitute one and the same instrument. A set of the copies of this
Fourth Amendment signed by the parties hereto shall be delivered to the Borrower
and the Administrative Agent. The execution and delivery of this Fourth
Amendment by any Lender shall be binding upon each of its successors and assigns
(including Transferees of its commitments and Loans in whole or in part prior to
effectiveness hereof) and binding in respect of all of its commitments and
Loans, including any acquired subsequent to its execution and delivery hereof
and prior to the effectiveness hereof.

     12. GOVERNING LAW. THIS FOURTH AMENDMENT AND THE RIGHTS AND OBLIGATIONS OF
THE PARTIES UNDER THIS FOURTH AMENDMENT SHALL BE GOVERNED BY, AND CONSTRUED AND
INTERPRETED IN ACCORDANCE WITH, THE LAW OF THE STATE OF NEW YORK WITHOUT REGARD
TO THE PRINCIPLES OF CONFLICTS OF LAWS THEREOF.

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     IN WITNESS WHEREOF, the parties hereto have caused this Fourth Amendment to
be executed and delivered by their respective duly authorized officers as of the
date first above written.



                                       CHS/COMMUNITY HEALTH SYSTEMS, INC.


                                       By: /s/ James W. Doucette
                                           -------------------------------------
                                           Name: James W. Doucette
                                           Title: Vice President and Treasurer



                                       COMMUNITY HEALTH SYSTEMS, INC.


                                       By: /s/ James W. Doucette
                                           -------------------------------------
                                           Name: James W. Doucette
                                           Title: Vice President and Treasurer



                                       THE CHASE MANHATTAN BANK, as
                                       Administrative Agent and Issuing Lender



                                       By: /s/ Dawn Lee Lum
                                           -------------------------------------
                                           Name: Dawn Lee Lum
                                           Title:


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