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                                                                    EXHIBIT 10.9

                              SUBLEASE AGREEMENT


          THIS SUBLEASE is made as of the 11/th/ day of May, 1999 by and between
HEALTHTRUST, INC. - THE HOSPITAL COMPANY, a Delaware corporation, successor by
merger to Medical Care America, Inc., a Delaware corporation ("Sublessor"), and
TRIAD HOSPITALS, INC., a Delaware corporation ("SubTenant"), under the following
circumstances:

          A. Pursuant to a certain Lease Agreement, dated November 12, 1992, as
amended by First Amendment to Lease Agreement, dated November 30, 1993, Second
Amendment to Lease Agreement, dated June 21, 1994, and Third Amendment to Lease
Agreement, dated January 20, 1995 (collectively, the "Prime Lease"), a copy of
which is attached hereto as Exhibit A, Two Galleria Tower Limited, a Texas
limited partnership ("Prime Lessor") has leased to Sublessor the premises
described therein (the "Premises").

          B. Sublessee desires to lease the premises leased under the Prime
Lease from Sublessor and Sublessor desires to lease the same to Sublessee, on
the terms and conditions set forth in this Sublease, and

          NOW, THEREFORE, in consideration of the covenants and agreements of
the parties hereinafter set forth and other good and valuable consideration,
receipt of which is hereby acknowledged by the parties, Sublessor and Sublessee
hereby agree as follows:

          1. Subleased Premises. Sublessor hereby subleases to the Sublessee of
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the premises described in the Prime Lease (hereinafter the "Subleased Premises")
consisting of approximately 22,248 square feet of Net Rentable Area located on
Floor 20 of the building known as Two Galleria Tower.

          2. Term. The term of this Sublease shall commence on May 11, 1999 and
             ----
terminate on January 31, 2003 (the "Term").

          3. Rent. Sublessee shall pay to Sublessor rent for the Subleased
             ----
Premises equal to all Rent (as defined in the Prime Lease) payable by Sublessor
under the Prime Lease.

          4. Assignment/Further Subletting. Sublessee shall not, either
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voluntarily or by operation of law, directly or indirectly sell, hypothecate,
assign or transfer this Sublease, in whole or in part, or further sublet all or
any part of the Subleased Premises, or permit the Subleased Premises to be
occupied by any other person, without the prior written consent of Sublessor and
Prime Lessor in each instance.

          Any sale, assignment, mortgage, transfer or subletting of this
Sublease, which is not in compliance with the provisions of this Paragraph 4
shall be void and at the option of Sublessor, Sublessor may terminate this
Sublease. Each such assignment, transfer or further subletting of the Subleased
Premises, if consented to by Sublessor and Prime Lessor shall be subject and
subordinate to the Prime Lease and this Sublease and each such assignee or
sublessee shall be bound to perform, observe and comply with all of the
covenants, agreements and terms and conditions of this Sublease, all of which
shall be specifically assumed in writing by such assignee or sublessee. Upon the
consummation of any such transfer, assignment or sublease, Sublessee shall
deliver to Sublessor promptly thereafter, a copy of the fully executed
assignment, sublease or other instrument of transfer. The consent of Sublessor
or Prime Lessor to any one
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assignment or sublease shall not relieve Sublessee or its assignee or subtenants
from obtaining the prior written consent of Prime Lessor and Sublessor to any
further assignment or subletting and shall not release Sublessee from any
liability or obligation hereunder, whether or not then accrued.

          5. Prime Lease. Sublessor represents that a true and complete copy of
             -----------
the Prime Lease, as amended, supplemented and modified, is attached hereto as
Exhibit A and Sublessee acknowledges receipt thereof. Sublessor represents and
warrants that the Prime Lease is in full force and effect and Sublessor has no
knowledge of any defaults under the Prime Lease. This Sublease is subject and
subordinate to the Prime Lease, all of the terms and conditions thereof and the
performance by Prime Lessor of all of its obligations thereunder, and to the
extent approved by Sublessee, which approval will not be unreasonably withheld,
all amendments and supplements hereafter entered into. All terms contained in
this Sublease shall have the same meanings and definitions ascribed to them in
the Prime Lease, unless any such term is expressly defined in this Sublease or
the context requires otherwise. Sublessee shall not commit or permit to be
committed on the Subleased Premises any act or omission which violates any term
or condition of the Prime Lease. In the event of the termination of the
Sublessor's interest as Sublessee under the Prime Lease for any reason other
than a default by Sublessor under the Prime Lease which occurs for any reason
other than a breach or a default by Sublessee under this Sublease, then this
Sublease shall terminate coincidentally therewith without any liability of
Sublessor to Sublessee. Sublessee shall only have such rights with respect to
the Leased Premises which Sublessor has pursuant to the Prime Lease. Except as
specifically exempted as provided below in this Paragraph 5, Sublessee shall
assume, perform and observe all of the obligations of Sublessor as Tenant under
the Prime Lease, to the extent that such terms and conditions are applicable to
the Subleased Premises, including without limitation thereto payment (or in the
case of payment in the first instance by Sublessor, reimbursement of Sublessor
for payment) of all rent which becomes due under the Prime Lease. Sublessee's
performance and observance of all such obligations shall be effected so that,
whenever time periods are specified in the Prime Lease for Sublessor's
compliance as Lessee thereunder, Sublessee shall have so complied on or prior to
such date, unless otherwise specifically provided herein. Except as otherwise
provided in this Sublease, all of the terms and conditions contained in the
Prime Lease, except for the provisions of 2.3, 3.3, 5.4, 6.17, 7.1, 7.2, 7.3,
and 7.4 are incorporated herein as terms and conditions of this Sublease (with
each reference in the Prime Lease to "Landlord" being deemed to refer to
Sublessor and Prime Lessor, with each reference to "Tenant" therein being deemed
to refer to Sublessee and with each reference to the Premises being deemed to
refer to the Subleased Premises); and all such provisions along with all of the
provisions specifically set forth in this Sublease, shall be the complete terms
and conditions of this Sublease.

          If Prime Lessor shall be in default of any of its obligations under
the Prime Lease, Sublessee shall be entitled to all rights and remedies against
Prime Lessor which Sublessor would otherwise be entitled to under the Prime
Lease as a result of such default; subject, however, to the following provisions
and procedures: Insofar as Prime Lessor is or may be obligated to construct or
make any alterations or improvements to the Subleased Premises, to furnish any
services to the Leased Premises, to repair or rebuild the same, to insure the
Subleased

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Premises, to perform any other act whatsoever with respect to the Premises or
the Subleased Premises or to perform any obligation or satisfy any condition
under the Prime Lease, Sublessee expressly acknowledges that notwithstanding
anything to the contrary provided in this Paragraph 5, Sublessor does not
undertake the performance or observance of such obligations, but is only
obligated to use reasonable efforts to obtain Prime Lessor's performance for
Sublessee's benefit and without obligating itself to institute legal action or
incur any out of pocket expense. If after receipt of written request from
Sublessee, Sublessor fails or refuses to take appropriate action for the
enforcement of Sublessor's rights against Prime Lessor with respect to the
Leased Premises, Sublessee shall have the right to take such action in
Sublessee's own name and for that purpose and only to such extent, Sublessor's
rights under the Prime Lease shall be and hereby are conferred upon and assigned
to Sublessee. Sublessee shall be subrogated to such rights to the extent that
the same shall apply to the Subleased Premises. If any such action against Prime
Lessor in Sublessee's name shall be barred by reason of lack of privity,
nonassignability or otherwise, Sublessor shall permit Sublessee to take such
action in Sublessor's name; provided, however, that Sublessee shall indemnify,
defend and hold Sublessor harmless from and against all liability, expense, loss
or damage which Sublessor may incur or suffer by reason of any such action, and
that copies of all papers, and notices of all proceedings, shall be given to
Sublessor.

          6. Defaults and Remedies. The following events of default and remedies
             ---------------------
shall govern this Sublease:

             (a) Defaults. The following events shall constitute a material
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default under this Sublease:

                 (i)   The failure by Sublessee to make any payment of rent or
any other payment required to be made by Sublessee hereunder, as and when due,
where such failure shall continue for a period of 10 days after written notice
thereof from Sublessor or Prime Lessor.

                 (ii)  The failure by Sublessee to observe or perform any of the
covenants, conditions or provisions of this Sublease to be observed or performed
by Sublessee other than those described in Section (i) above, where such failure
shall continue for a period of 30 days after written notice thereof from
Sublessor or Prime Lessor, provided that if the cure of such breach shall
reasonably require more than 30 days, then Sublessee shall not be in default if
Sublessee commenced such cure within said 30 day period and thereafter
diligently prosecutes such cure to completion.

                 (iii) The making by Sublessee of any general assignment, or
general arrangement for the benefit of creditors; the filing by or against
Sublessee of a petition to have Sublessee adjudged a bankrupt or a petition for
reorganization or arrangement under any bankruptcy law (unless the petition
filed against Sublessee is dismissed within 90 days); the appointment of a
trustee or receiver to take possession of substantially all of Sublessee's
assets located at the Subleased Premises or of Sublessee's interest in this
Sublease, where possession is not restored to Sublessee within 30 days; or the
attachment, execution or other judicial seizure of substantially all of
Sublessee's assets located at the Subleased Premises or of Sublessee's interest
in this Sublease, where such seizure is not discharged within 60 days.

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          (b) Remedies. In the event of any such material default, Sublessor may
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at any time thereafter, and without limiting Sublessee in the exercise of any
right or remedy which Sublessor may have by reason of such default:

              (i)     Terminate Sublessee's right to possession of the Subleased
Premises by any lawful means, in which case this Sublease shall terminate and
Sublessee shall immediately surrender possession of the Subleased Premises to
Sublessor. In which event Sublessor shall be entitled to recover from Sublessee
all damages incurred by Sublessor by reason of Sublessee's default including,
but not limited to, the cost of recovering possession of the Subleased Premises;
expenses of reletting, including renovation and alteration of the Subleased
Premises, reasonable attorney's fees, and any real estate commissions actually
paid; the worth at the time of award of the amount by which the unpaid rent for
the balance of the term after the time of such award exceeds the amount of such
rental loss for the same period that Sublessee proves could be reasonably
avoided; and that portion of any leasing commission paid by Sublessor applicable
to the unexpired term of this Sublease. Unpaid installments of Rent or other
sums shall bear interest from the date due at the "prime rate" of interest as
announced from time to time in the Wall Street Journal plus 5%, but in no event
more than the maximum interest allowed by law (which rate is hereinafter
referred to as the "Interest Rate"). If Sublessee abandons the Subleased
Premises, Sublessor shall have the option of retaking possession of the
Subleased Premises and recovering from Sublessee the amount as specified in this
paragraph.

              (ii)    Maintain Sublessee's right to possession in which case
this Sublease shall continue in effect whether or not Sublessee shall have
abandoned the Subleased Premises. In such event, Sublessor shall be entitled to
enforce all of Sublessor's rights and remedies under this Sublease, including
the right to recover the rent as it becomes due hereunder.

              (iii)   Sublessor may remove any or all items of Sublessee's
property from the Subleased Premises and dispose of them in any commercially
reasonable manner, and Sublessee shall pay upon demand to Sublessor the actual
expense of such removal and disposition together with interest at the Interest
Rate, but in no event more than the maximum interest allowed by law, from the
date of payment by Sublessor until repayment by Sublessee.

              (iv)    Pursue any other remedy now or hereafter available to
Sublessor under the laws or judicial decisions of the State of Texas.

          7.  Notices. Any notice or other communication required or permitted
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to be given under this Sublease shall be in writing and shall be deemed to have
been effectively given if delivered personally or if mailed certified mail,
postage prepaid, return receipt requested, or sent by nationally recognized
overnight carrier as follows:

          If to Sublessor:

                  Healthtrust, Inc. - The Hospital Company
                  One Park Plaza
                  Building 2, 5th Floor
                  Nashville, TN 37203

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                Attn.  Real Estate Department


          If to Sublessee:

                Triad Hospitals, Inc.
                2000 Two Galleria Tower
                13455 Noel Road
                Dallas, Texas 75240

          Any party may change the address to which notices and other
communications are to be directed to it by giving notice of such change to the
other party in the manner provided in this section.

          8.    Parking. Sublessee shall be entitled to Parking Permits for
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the following number and type of parking spaces in the Garage and shall pay the
following parking fees:

                                    No. of Spaces Monthly Fee
                                    ------------- -----------

          General Parking Area:     24                  -0-

          Executive Parking Area:   40                  -0-

          VIP Parking Area:         12                  -0-

          9.    Headings. The use of headings, captions and numbers in this
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Sublease is solely for the convenience of identifying and indexing the various
paragraphs, and shall in no event be considered otherwise in construing or
interpreting any provision of this Sublease.


          10.   Severability. If any term, covenant, conditions or provision
                ------------
of this Sublease, or the application thereof to any person or circumstance shall
ever be held to be invalid or unenforceable, then, in each such event, the
remainder of this Sublease or the application of such term, covenant, condition
or provision to any other person or any other circumstances (other than those as
to which it shall be invalid or unenforceable) shall not be thereby affected,
and each term, covenant, condition and provision hereof shall remain valid and
enforceable to the fullest extent provided by law.

          11.   Entire Agreement. This Sublease (including the Exhibits, the
                ----------------
Prime Lease and all supplementary agreements provided for herein, if any)
contains the entire agreement of the Sublessor and the Sublessee and no
representations, warranties, inducements, promises or agreements, oral or
otherwise, between the parties not described in this Sublease shall be of any
force or effect.

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          12.   Modifications. This Sublease shall not be modified or amended in
                -------------
any respect except by a written agreement executed by the Sublessor and the
Sublessee in the same manner as this Sublease is executed.

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          IN WITNESS WHEREOF, Sublessor and Sublessee have executed this
instrument as of the day and year first written above.

                              SUBLESSOR:


                              HEALTHTURST, INC. - THE HOSPITAL COMPANY, a
                              Delaware corporation, successor by merger to
                              Medical Care America, Inc.


                              By:   /s/  Howard Patterson
                                   -----------------------

                              Title: Vice President


                              SUBLESSEE:

                              TRIAD HOSPITALS, INC.


                              By:   /s/  Donald P. Fay
                                   --------------------

                              Title: Executive Vice President, General Counsel
                                      and Secretary