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                                                                 EXHIBIT 10.4

                              EMPLOYMENT AGREEMENT

      This EMPLOYMENT AGREEMENT (the "Agreement") is made and entered into as of
July 1, 2004 by and between AHS Management Company, Inc., a Delaware corporation
(the "Company"), and David T. Vandewater, an individual ("Employee").

                                   WITNESSETH:

      WHEREAS, the Company desires to enter into this Agreement with Employee
and to provide him with the benefits set forth herein in recognition of the
valuable services he has rendered and will continue to render to the Company,
and for the purposes evidenced herein;

      WHEREAS, Employee is ready and willing to continue to render the services
provided for, and on the terms and conditions set forth herein, and he is
willing to refrain from activities competitive with the business of the Company
during the term of and after this Agreement on the terms and conditions set
forth herein;

      WHEREAS, in serving as an employee of the Company, Employee will
participate in the use and development of confidential proprietary information
about the Company, its customers and suppliers, and the methods used by the
Company and its employees in competition with other companies, as to which the
Company desires to protect fully its rights;

      NOW, THEREFORE, in consideration of the premises and the mutual covenants
and agreements herein set forth, the parties hereto agree as follows:

      1.    Employment. The Company hereby employs Employee and Employee accepts
such employment with the Company, subject to the terms and conditions set forth
herein. Employee shall be employed as President and Chief Executive Officer and
shall perform all duties and services incident to such position, and such other
similar duties and services as may be prescribed by the Bylaws of the Company or
established by the Chairman of the Board of Directors (the "Board") of the
Company, or its parent corporation from time to time. During his employment
hereunder, Employee shall devote his best efforts and attention, on a full-time
basis, to the performance of the duties required of him as an employee of the
Company.

      2.    Principal Office. Employee's principal office and normal place of
work shall be at the Company's principal executive offices in Nashville,
Tennessee ("Principal Office").

      3.    Compensation.

            (a)   As compensation for services rendered by Employee hereunder,
      Employee shall receive:

                  (1)   Salary. An annual salary of $450,000, or such higher
            salary as shall be approved by the Board from time to time, which
            shall be payable in arrears in equal monthly installments
            ("Salary").

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                  (2)   Bonus. The Company shall pay Employee an annual cash
            bonus in an amount to be determined by the Board based on whether
            certain reasonable objectives established by the Board prior to the
            beginning of each fiscal year as set forth in the Company's
            Incentive Compensation Plan (the "Plan") have been met. Such bonus
            and objectives may be stated in a written incentive compensation
            program which the Company intends to qualify as "performance based
            compensation" described in Internal Revenue Code section 162(m). The
            bonus payable during the first year, beginning January 1, 2004,
            shall be 100% of Employee's Salary if the Plan objectives have been
            met, and 125% of Salary if the Plan is met and exceeded by 10% or
            more. Thereafter, Employee shall be a full participant in the Plan
            as adopted each year by the Board.

                  (3)   Fringe Benefits. Employee shall be entitled during the
            Term of this Agreement (as defined below) to such other benefits of
            employment with Employer as are now or may hereafter be in effect
            for Employer's senior executives with duties comparable to Employee
            including, without limitation, all incentive and deferred
            compensation, pension, life and other insurance, disability (insured
            and uninsured), medical and dental and other benefit plans or
            programs, paid time off and stock option grants as approved by the
            Board. Without limiting the foregoing, the Company shall (i) provide
            Employee with not fewer than thirty (30) hours of usage of the
            Company's airplane for personal use (as compared to business travel)
            at a cost of $1,800.00 per flight hour (which is the cost of such
            usage to the Company), (ii) continue to provide Employee with two
            executive disability income coverage policies with all premiums paid
            by the Company, (iii) continue to provide Employee with a $5,000,000
            life insurance policy on Employee's life for the remaining term of
            such policy with all premiums to be paid by the Company, and with
            such policy to be owned by Employee or Employee's designee, and (iv)
            advance to Employee all premiums due with respect to a $10,000,000
            second-to-die life insurance policy insuring the joint lives of
            Employee and Employee's spouse, with such policy to be owned by
            Employee or Employee's designee. In addition to advancing the
            premiums on the second-to-die insurance policy, Employee shall be
            entitled to receive an additional payment in an amount such that
            after payment by Employee of all taxes, including income taxes, and
            taking into account any withholding obligation on the part of the
            Company, Employee retains an amount equal to the premiums due on
            such life insurance policy. The Company's obligation to make
            advances to Employee for the premiums due on the second-to-die
            insurance policy shall continue notwithstanding Employee's death.

                  (4)   Expenses. During the Term of this Agreement, Employer
            shall reimburse Employee promptly for all reasonable travel,
            entertainment, parking, business meeting and similar expenditures in
            pursuance and furtherance of Employer's business upon receipt of
            reasonable supporting documentation as required by Employer's
            policies applicable to its officers and other key employees
            generally.

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                  (5)   Withholdings. All amounts payable to Employee hereunder
            shall be subject to such deductions or withholdings as are required
            by law or the policies of the Company or as may be authorized or
            directed by Employee.

            (b)   Benefits Review. Prior to the end of each fiscal year of the
      Company, the Board shall review Employee's salary and benefits payable
      hereunder. Any increases in salary or changes in fringe benefits
      determined by the Board at such annual review shall become effective the
      following month unless otherwise determined by the Company. Employee
      understands and acknowledges that the opportunity of an annual salary and
      benefit review by the Board shall not be construed in any manner as an
      express or implied agreement by the Company to raise or increase his
      salary or benefits.

            (c)   Indemnification. This Agreement hereby incorporates and makes
      a part of this agreement the Indemnification Agreement dated February
      2002, by and between Employee and Ardent Health Services LLC. The
      provisions and rights guaranteed under that Agreement shall survive any
      termination of this Agreement.

      4.    Confidential Information and Trade Secrets.

            (a)   Trade Secrets. Employee recognizes that Employee's position
      with the Company requires considerable responsibility and trust, and, in
      reliance on Employee's loyalty, the Company may entrust Employee with
      highly sensitive confidential, restricted and proprietary information
      involving Trade Secrets and Confidential Information. For purposes of this
      Agreement, a "Trade Secret" is any scientific or technical information,
      design, process, procedure, formula or improvement that is valuable and
      not generally known to competitors of the Company. "Confidential
      Information" is any data or information, other than Trade Secrets, that is
      important, competitively sensitive, and not generally known by the public,
      including, but not limited to, the Company's business plan, acquisition
      targets, training manuals, product development plans, pricing procedures,
      market strategies, internal performance statistics, financial data,
      confidential personnel information concerning employees of the Company,
      supplier data, operational or administrative plans, policy manuals, and
      terms and conditions of contracts and agreements. The terms "Trade Secret"
      and "Confidential Information" shall not apply to information which is (1)
      made available to the general public without restriction by the Company,
      (2) obtained from a third party by Employee in the ordinary course of
      Employee's employment by the Company, or (3) required to be disclosed by
      Employee pursuant to subpoena or other lawful process, provided that
      Employee notifies the Company in a timely manner to allow the Company to
      appear to protect its interests.

            (b)   Non-disclosure. Except as required to perform Employee's
      duties hereunder, Employee will not use or disclose any Trade Secrets or
      Confidential Information of the Company during employment, or at any time
      after termination of employment and prior to such time as they cease to be
      Trade Secrets or Confidential Information through no act of Employee in
      violation of this Agreement.

            (c)   Material Surrender. Upon termination of Employee's employment
      with the Company, Employee will surrender to the Company all files,
      correspondence,

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      memoranda, notes, records, manuals or other documents or data pertaining
      to the Company's business or Employee's employment (including all copies
      thereof) however prepared and whether maintained in paper or electronic
      format. Employee will also leave with the Company all materials involving
      any Trade Secrets or Confidential Information of the Company. All such
      information and materials, whether or not made or developed by Employee,
      shall be the sole and exclusive property of the Company, and Employee
      hereby assigns to the Company all of Employee's right, title and interest
      in and to any and all of such information and materials.

      5.    Covenants. Employee shall be subject to the following covenants and
obligations:

            (a)   Non-competition covenant. While employed by the Company,
      Employee shall not compete or plan or prepare to compete with the Company
      regarding the ownership, investment in, management of or operation of free
      standing hospitals that provide either medical-surgical and/or behavioral
      healthcare services ("Hospital"). Employee shall not compete with the
      Company for a period of eighteen (18) months following the termination of
      his employment, within thirty (30) miles of any location where (1) the
      Company owned, operated or managed any Hospital either on the date his
      employment terminates or at any time within the immediately preceding
      fiscal year or (2) the Board had approved the potential or final
      acquisition of any Hospital prior to his termination and Employee had
      knowledge of said approval.

            (b)   Non-solicitation covenant. Following the termination of
      Employee's employment with the Company, for a period equal to the term of
      the non-competition covenant under Section 5(a), Employee shall not
      directly or indirectly solicit the services of or otherwise induce or
      attempt to induce any Company Employee to sever his/her employment
      relationship with the Company. For purposes of this section "Company
      Employee" shall mean (1) any employee who performs or performed (on the
      Termination Date or within the previous six (6) months of such date) any
      of his/her services at the Company's Principal Office and (2) any member
      of the senior management staff of any line of hospital based healthcare
      business owned, operated or managed by the Company. Prior to the
      initiation of any conduct prohibited under this Section, Employee may
      request that the Company waive application of this Section to said
      conduct. Granting of such request, however, shall be at the Company's sole
      discretion.

            (c)   Scope and Duration; Severability. The Company and Employee
      understand and agree that the scope and duration of the covenants
      contained in this Section 5 are reasonable both in time and geographical
      area and are fairly necessary to protect the business of the Company.
      Except as otherwise stated herein, such covenants shall survive the
      termination of Employee's employment. It is further agreed that such
      covenants shall be regarded as divisible and shall be operative as to time
      and geographical area to the extent that they may be made so and, if any
      part of such covenants are declared invalid or unenforceable, the validity
      and enforceability of the remainder shall not be affected.

            (d)   Assignment. Employee agrees that the covenants contained in
      this Section 5 shall inure to the benefit of any successor or assign of
      the Company, with the

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      same force and effect as if such covenant had been made by Employee with
      such successor or assign.

            (e)   Exclusion. Notwithstanding the provisions of this Section 5,
      Employee's non-competition obligations shall not preclude Employee from
      owning less than one percent (1%) of the voting power or common interest
      in any publicly traded corporation conducting business activities in the
      healthcare industry in competition with the Company or any affiliate.

            (f)   Company. For purposes of this Section 5, "Company" shall mean
      Ardent Health Services LLC, Ardent Health Services, Inc., AHS Management
      Company, Inc. and Ardent Medical Services, Inc.

      6.    Program Participation. Employee represents that he is, and will for
the term of this Agreement be eligible to participate in Medicare, Medicaid,
CHAMPUS, TriCare, and other federal health programs, and Employee shall not have
been sanctioned by the Health and Human Services Office of the Inspector
General, Cumulative Sanctions Report, or excluded by the General Services
Administration, as set forth on the List of Excluded Providers [see
www.dhhs.gov/progorg/oig and www.arnet.gov/epis].

      7.    Specific Enforcement. Employee specifically acknowledges and agrees
that the restrictions set forth in Sections 4 and 5 hereof are reasonable and
necessary to protect the legitimate interests of the Company and that the
Company would not have entered into this Agreement in the absence of such
restrictions. Employee further acknowledges and agrees that any violation of the
provisions of Sections 4 and 5 hereof will result in irreparable injury to the
Company, that the remedy at law for any violation or threatened violation of
such Sections will be inadequate and that in the event of any such breach, the
Company, in addition to any other remedies or damages available to it at law or
in equity, shall be entitled to temporary injunctive relief before trial from
any court of competent jurisdiction as a matter of course and to permanent
injunctive relief without the necessity of proving actual damages. The Company
shall also have available all remedies provided under state and federal
statutes, rules and regulations as well as any and all other remedies as may
otherwise be contractually or equitably available. In addition to any other
remedy herein granted or available to Company, either at law or in equity,
Employee shall forfeit and forever release any claim or right Employee may have
to any benefits remaining under this Agreement from the date Employee breached
Section 5 of this Agreement. Any monetary damages sought by the Company under
this Section shall not include the benefits forfeited under this Section.

      8.    Term. This Agreement shall continue for four (4) years from the date
first written above ("Initial Term"), unless sooner terminated in the manner set
forth herein; provided, however, that following the Initial Term, this Agreement
shall automatically renew at the end of the Initial Term for additional terms of
one (1) year (collectively the "Term") unless either party gives notice of
termination to the other not later than thirty (30) days prior to any annual
anniversary of this Agreement (a "Notice of Non-Renewal"). The date upon which
this Agreement and Employee's employment hereunder shall terminate, whether
pursuant to the terms of this Section or pursuant to any other provision of this
Agreement shall hereafter be referred to as the "Termination Date."

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      9.    Non-Renewal Termination. In the event this Agreement terminates
pursuant to a Notice of Non-Renewal, the Company shall have no further
obligation to Employee and Employee shall have no further rights or obligations
hereunder except that if the Company is the non-renewing party, the Company
shall be obligated to pay Employee, as severance compensation, the salary and
benefits set forth in Sections 14(b) and (c) of this Agreement. Employee's
obligations under Section 4 hereof shall survive the termination of this
Agreement pursuant to a Notice of Non-Renewal by either party. Notwithstanding
anything to the contrary herein, Employee's obligations under Section 5 hereof
shall only apply for twelve (12) months if the Company is the non-renewing
party, but shall continue in full force and effect if Employee is the
non-renewing party.

      10.   Termination Upon Death of Employee. Except as set forth in Section
3(a)(3)(iii) hereof, in the event Employee dies during the Term of this
Agreement, this Agreement shall immediately terminate and neither Employee nor
the Company shall have any further obligations hereunder.

      11.   Termination by Employee For Cause. Employee may terminate this
Agreement thirty (30) days after delivery to the Board of Managers of Ardent
Health Services LLC of written notice of his intent to terminate this Agreement,
which notice alleges the occurrence of: (a) a material diminution in Employee's
office, duties or responsibilities, (b) a material change in the personnel at
Welsh, Carson, Anderson & Stowe, IX, L.P. with whom the Company has its primary
working relationship, or (c) a material breach by the Company of this Agreement.
Notwithstanding the foregoing, however, Employee shall not have the ability to
terminate this Agreement if the facts alleged in such written notice have been
cured prior to the expiration of such thirty (30) day notice period. In the
event Employee's employment hereunder is terminated in accordance with this
Section, the Company shall have no further obligation to Employee and Employee
shall have no further rights or obligations hereunder, except as set forth in
Section 4 above, and except for the Company's obligation to pay Employee, as
severance compensation, the salary and benefits set forth in Sections 14(b) and
(c) of this Agreement. Notwithstanding anything to the contrary herein, in the
event of a termination pursuant to this Section, Employee shall have no
obligations under Section 5 hereof from and after the Termination Date.

      12.   Termination by the Company for Cause. The Company shall have the
right at any time to terminate Employee's employment immediately for cause. The
term "Cause" shall mean (a) Employee's willful refusal to perform, or gross
negligence in performing, the reasonable duties of Employee's office delegated
under Section 1 of this Agreement, (b) Employee's conviction of or guilty plea
to any crime punishable as a felony, or involving fraud or embezzlement, (c)
Employee's change in status under Section 6 of this Agreement, (d) any act by
Employee involving moral turpitude that materially affects the performance of
his duties hereunder, or (e) Employee's use of chemical substances in a manner
that materially affects the performance of his duties hereunder. Employee's
obligations under Sections 4 and 5 hereof shall survive in full force and effect
the termination of the Agreement pursuant to this Section 11. In the event
Employee's employment hereunder is terminated in accordance with this Section,
the Company shall have no further obligation to make any payments to Employee
hereunder except for unpaid salary or unreimbursed expenses that have accrued
but have not been paid as of the Termination Date.

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      13.   Termination Without Cause.

            (a)   In the event that Employee is terminated by the Company
      without cause during the Term hereof (which shall not include a
      termination pursuant to Sections 10, 11, 12, 14 or 15), the Company shall:
      (1) pay Employee all bonuses and unreimbursed expenses owed to Employee
      that have accrued but have not been paid as of the Termination Date; and
      (2) pay to Employee, as severance compensation, the salary and benefits
      set forth in Sections 14(b) and (c) of this Agreement. Employee's
      obligations under Section 4 hereof shall survive the termination of this
      Agreement pursuant to this Section. Notwithstanding anything to the
      contrary herein, in the event of a termination pursuant to this Section,
      Section 5 shall apply in full force and effect for only twelve (12) months
      from the Termination Date.

            (b)   In the event that Employee terminates his employment with the
      Company without cause during the term hereof (which shall not include a
      termination pursuant to Sections 10, 11, 12, 14 or 15), the Company shall
      only be obligated to pay Employee any salary and unreimbursed expenses
      owed to Employee that have accrued but have not been paid as of the
      Termination Date. Employee's obligations under Sections 4 and 5 hereof
      shall survive in full force and effect the termination of the Agreement
      pursuant to this Section 12(b).

      14.   Termination Upon a Change in Control. Employee shall have the
unilateral right, to be exercised or not in his sole discretion, to terminate
this Agreement under this Section 14 within three hundred sixty (360) days after
a Change in Control (as such term is hereinafter defined). Notwithstanding any
statement contained in this Agreement to the contrary (other than in Section
12), in the event of Employee's termination of this Agreement for any reason
within three hundred sixty (360) days following a Change in Control, Employee
shall be entitled to the compensation and benefits described in Section 14(b)
and (c). Employee's obligations under Sections 4 and 5 hereof shall survive in
full force and effect the termination of the Agreement pursuant to this Section
14.

            (a)   For purposes of this Agreement, a Change in Control means the
      occurrence of any of the following events, provided that references to the
      Company in this Section 14(a) shall be treated as a reference solely to
      Ardent Health Services, Inc. and/or Ardent Health Services LLC, and shall
      not be treated as a reference to solely the behavioral hospital operations
      of the Company:

                  (1)   An acquisition (other than directly from the Company) of
            any voting securities of the Company (the "Voting Securities") by
            any "Person" (as that term is used for purposes of Section 13(d) or
            14(d) of the Securities Exchange Act of 1934, as amended (the
            "Exchange Act")), immediately after which such Person has
            "Beneficial Ownership" (within the meaning of Rule 13d-3 promulgated
            under the Exchange Act) of more than fifty percent (50%) of the
            combined voting power of the Company's then outstanding voting
            Securities; provided, however, in determining whether a Change in
            Control has occurred, Voting Securities which are acquired in a
            Non-Control Acquisition shall not constitute an acquisition which
            would cause a Change in Control. A "Non-

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            Control Acquisition" shall mean an acquisition by (i) an employee
            benefit plan (or a trust forming a part thereof) maintained by (A)
            the Company, or (B) any corporation or other Person of which a
            majority of its voting power or its voting equity securities or
            equity interest is owned, directly or indirectly, by the Company
            (for purposes of this definition, a "Subsidiary"), (ii) the Company
            or its Subsidiaries, or (iii) any person in connection with a
            Non-Control Transaction (as hereinafter defined);

                  (2)   The individuals who, as of the date of this Agreement,
            are members of the Board (the "Incumbent Board"), cease for any
            reason to constitute at least a majority of the members of the
            Board; provided, however, that if the election, or nomination for
            election by the Company's equity holders, of any new director was
            approved by a vote of at least a majority of the Incumbent Board,
            such new director shall, for purposes of this Agreement, be
            considered as a member of the Incumbent Board; provided, further,
            however, that no individual shall be considered a member of the
            Incumbent Board if such individual initially assumed office as a
            result of either an actual or threatened "Election Contest" (as
            described in Rule l4a-l 1 promulgated under the Exchange Act) or
            other actual or threatened solicitation of proxies or consents by or
            on behalf of a Person other than the Board (a "Proxy Contest")
            including by reason of any agreement intended to avoid or settle any
            Election Contest or Proxy Contest; or

                  (3)   Approval by the holders of the Voting Securities of the
            Company of:

                        (i)   A merger, consolidation or reorganization
                  involving the Company, unless such merger, consolidation or
                  reorganization is a Non-Control Transaction. A "Non-Control
                  Transaction" shall mean a merger, consolidation or
                  reorganization of the Company where:

                           A)       the holders of the Voting Securities of the
                        Company, immediately before such merger, consolidation
                        or reorganization, own directly or indirectly
                        immediately following such merger, consolidation or
                        reorganization, more than fifty percent (50%) of the
                        combined voting power of the outstanding voting
                        securities of the entity resulting from such merger or
                        consolidation or reorganization (the "Surviving Entity")
                        in substantially the same proportion as their own
                        ownership of the Voting Securities immediately before
                        such merger, consolidation or reorganization; and

                           B)       the individuals who were members of the
                        Incumbent Board immediately prior to the execution of
                        the agreement providing for such merger, consolidation
                        or reorganization constitute at least a majority of the
                        members of the board of directors of the Surviving
                        Entity, or a corporation or

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                        entity beneficially directly or indirectly owning a
                        majority of the Voting Securities of the Surviving
                        Entity;

                        (ii)  A complete liquidation or dissolution of the
                  Company; or

                        (iii) An agreement for the sale or other disposition of
                  all or substantially all of the assets of the Company to any
                  Person (other than a transfer to (x) a Subsidiary or (y) any
                  Principal or Related Party of a Principal).

                  (4)   Any transaction by which any organization other than
            Welsh, Carson, Anderson & Stowe, IX, L.P. and any Related Party
            shall cease to own more than fifty percent (50%) of the Voting
            Securities.

      For purposes of this Section 14, the following defined terms have the
following meanings:

      "Principals" means (i) Welsh, Carson, Anderson & Stowe, IX, L.P., (ii) FFC
Partners II, L.P., (iii) BancAmerica Capital Investors I, L.P., (iv) any
investment fund under common control or management with any person in the
foregoing clauses (i), (ii) or (iii), and (v) any general partner or other
entity directly controlling or managing any person in the foregoing clauses (i)
through (iv).

      "Related Party" means:

            (1)   any controlling stockholder, partner, member, 80% (or more)
      owned Subsidiary, or immediate family member (in the case of an
      individual) of any Principal; or

            (2)   any trust, corporation, partnership or other entity, the
      beneficiaries, stockholders, partners, owners or persons beneficially
      holding an 80% or more controlling interest of which consist of any one or
      more Principals and/or such other persons referred to in the immediately
      preceding clause (1).

            Notwithstanding the foregoing, a Change in Control shall not be
      deemed to occur solely because any Person (the "Subject Person") acquired
      Beneficial Ownership of more than the permitted amount of the then
      outstanding Voting Securities as a result of the acquisition of Voting
      Securities by the Company which, by reducing the number of Voting
      Securities then outstanding, increases the proportional number of shares
      Beneficially Owned by the Subject Person, provided that if a Change in
      Control would occur (but for the operation of this sentence) as a result
      of the acquisition of Voting Securities by the Company, and after such
      share acquisition by the Company, the Subject Person becomes the
      Beneficial Owner of any additional voting Securities which increases the
      percentage of the then outstanding Voting Securities Beneficially Owned by
      the Subject Person, then a Change in Control shall occur.

            (b)   Severance Amount. Employee shall receive as severance benefits
      under this Section 14 three (3) times the highest salary and bonus level
      in effect for Employee

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      at any time during the Term of this Agreement. Employee shall also receive
      a cash amount equivalent of three (3) years of fringe benefits as
      described in Section 3(a)(3) in effect as of the Termination Date.
      Employee shall also be entitled to receive reasonable attorney's fees and
      costs incurred in making a successful claim for compensation and benefits
      hereunder, including all costs of arbitration, mediation, or litigation,
      if necessary.

            (c)   Schedule of Payments. The Company will make cash payments due
      under this Section 14 in the manner described below following Employee's
      termination of employment. All other amounts and allowances will be
      provided or promptly paid upon submission of receipts or other evidence of
      expenses eligible for reimbursement.

                  (1)   All cash and benefits will be paid over forty-eight (48)
            months, beginning on the first day of the month following the
            Termination Date.

                  (2)   In the event of the death of Employee prior to the
            payment of all cash due hereunder, all remaining payments may, at
            the Company's sole discretion either continue to be paid in
            accordance with Section 14(c) or be made in a single sum to
            Employee's surviving spouse. If Employee is not married at the time
            of death, such cash payments may be made to Employee's estate.

      15.   Disability of Employee.

            (a)   In the event Employee becomes disabled during the Term of this
      Agreement, the Company will continue to pay Employee according to the
      compensation provisions of this Agreement during the period of his
      disability, until such time as Employee's long term disability insurance
      benefits become available. However, in the event Employee is disabled for
      more than six (6) continuous months, the Company may terminate Employee's
      employment. In this case, the compensation provided for under this
      Agreement will cease, except for earned but unpaid Salary and Plan awards
      and other benefits and unreimbursed expenses that would be payable on a
      pro-rated basis for the fiscal year in which the disability occurred.

            (b)   During the period Employee is disabled but is receiving
      payments of regular compensation described in this Agreement and as long
      as he is physically and mentally able to do so, Employee will furnish
      information and assistance to the Company and from time to time will make
      himself reasonably available to the Company to undertake assignments
      consistent with his prior position with the Company and his physical and
      mental health. If the Company fails to make a payment or provide a benefit
      required as part of this Agreement, Employee's obligation to furnish
      information and assistance will end immediately.

            The term "Disability" shall mean the inability of Employee to
      perform the duties of his employment due to physical or emotional
      incapacity or illness (including, without limitation, alcohol or chemical
      dependency), where such inability has continued or is expected to continue
      for more than one hundred eighty (180) days in any one (1) year period. In
      the event of a dispute, the determination of Disability shall be made as
      follows: the Company and Employee (or his executor or personal
      representative, as the case may

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      be) shall each appoint a physician competent in the field of medicine to
      which such incapacity or illness relates, and two physicians so selected
      shall select a third physician who shall be similarly competent. The
      decision of a majority of such physicians as to the Disability of Employee
      shall be binding on the parties hereto.

      16.   Assignment.

            (a)   The rights and benefits of Employee under this Agreement,
      other than accrued and unpaid amounts due under Section 3(a) hereof, are
      personal to him and shall not be assignable. Discharge of Employee's
      undertakings in Section 4(c) hereof shall be an obligation of Employee's
      executors, administrators, or other legal representatives or heirs.

            (b)   This Agreement may not be assigned by the Company except to an
      affiliate of the Company, provided, however, that if the Company shall
      merge or effect a share exchange with or into, or sell or otherwise
      transfer substantially all its assets to, another corporation, the Company
      may assign its rights hereunder to that corporation.

      17. Notices. Any notice or other communications under this Agreement shall
be in writing, signed by the party making same, and shall be delivered
personally or sent by certified or registered mail, postage prepaid, addressed
as follows:

      If to Employee:                     David T. Vandewater
                                          425 Jackson Boulevard
                                          Nashville, Tennessee  37205

      If to the Company:                  AHS Management Company, Inc.
                                          Attention: General Counsel
                                          One Burton Hills Boulevard, Suite 250
                                          Nashville, Tennessee 37215

or to such other address as may hereafter be designated by either party hereto.
All such notices shall be deemed given on the date personally delivered or
mailed.

      18.   Governing Law. This Agreement shall be interpreted and enforced in
accordance with the laws of the State of Tennessee, without giving effect to the
choice of law provisions of such State.

      19.   Arbitration and Waiver of Jury Trial. Any dispute among the parties
hereto shall be settled by arbitration in Nashville, Tennessee, in accordance
with the then applicable rules of the Model Employment Arbitration Procedures of
American Arbitration Association and judgment upon the award rendered may be
entered in any court having jurisdiction thereof. The arbitrator shall award all
costs, legal expenses and fees to the successful party. The Company and Employee
each hereby waive any right to trial by jury of any dispute arising under this
Agreement.

      20.   Severability. Whenever possible, each provision of this Agreement
shall be interpreted in such manner as to be effective and valid, but if any one
or more of the provisions

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<PAGE>

contained in this Agreement shall be invalid, illegal or unenforceable in any
respect for any reason, the validity, legality and enforceability for any such
provisions in every other respect and of the remaining provisions of this
Agreement shall not be in any way impaired.

      21.   Modification. No waiver or modification of this Agreement or of any
covenant, condition, or limitation herein contained shall be valid unless in
writing and duly executed by the party to be charged therewith and no evidence
of any waiver or modification shall be offered or received in evidence of any
proceeding, arbitration or litigation between the parties hereunder, unless such
waiver or modification is in writing, duly executed as aforesaid and the parties
further agree that the provisions of this section may not be waived except as
herein set forth.

      22.   Entire Agreement. This Agreement contains the entire agreement of
the parties hereto with respect to the subject matter contained herein. There
are no restrictions, promises, covenants or undertakings, other than those
expressly set forth herein. This Agreement supersedes all prior agreements and
understandings between the parties with respect to such subject matter.

      23.   Employer Policies, Regulations and Guidelines for Employee. Employer
may issue policies, rules, regulations, guidelines, procedures or other
informational material, whether in the form of handbooks, memoranda, or
otherwise, relating to its employees. These materials are general guidelines for
Employee's information and shall not be construed to alter, modify or amend this
Agreement for any purpose whatsoever.

      IN WITNESS WHEREOF, the undersigned have executed this Agreement on the
day and year first above written.

                                           AHS MANAGEMENT COMPANY, INC.

                                           By: /s/ Stephen C. Petrovich
                                               ---------------------------------
                                           Title: Senior Vice President
                                                  General Counsel and Secretary

                                           EMPLOYEE

                                           /s/ David T. Vandewater
                                           -------------------------------------
                                           David T. Vandewater

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