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                                                                   EXHIBIT 10.23

                                JOINDER AGREEMENT

            THIS JOINDER AGREEMENT (the "Agreement"), effective as of November
5, 2004, is by and between MOUNTAIN VISTA MEDICAL CENTER, LP, a Delaware limited
partnership (the "Subsidiary"), and BANK OF AMERICA, N.A., in its capacity as
Administrative Agent under that certain Amended and Restated Credit Agreement
(as it may be amended, modified, restated or supplemented from time to time, the
"Credit Agreement"), dated as of June 22, 2004, by and among IASIS HEALTHCARE
LLC, a Delaware limited liability company (the "Borrower"), the Guarantors, the
Lenders and Bank of America, N.A., as Administrative Agent, Swingline Lender and
L/C Issuer. All of the defined terms in the Credit Agreement are incorporated
herein by reference.

            The Loan Parties are required by Section 7.11 of the Credit
Agreement to cause the Subsidiary to become a "Guarantor".

            Accordingly, the Subsidiary hereby agrees as follows with the
Administrative Agent, for the benefit of the Lenders:

            1. The Subsidiary hereby acknowledges, agrees and confirms that, by
its execution of this Agreement, the Subsidiary will be deemed to be a party to
the Credit Agreement and a "Guarantor" for all purposes of the Credit Agreement,
and shall have all of the obligations of a Guarantor thereunder as if it had
executed the Credit Agreement. The Subsidiary hereby ratifies, as of the date
hereof, and agrees to be bound by, all of the terms, provisions and conditions
applicable to the Guarantors contained in the Credit Agreement. Without limiting
the generality of the foregoing terms of this paragraph 1, the Subsidiary hereby
jointly and severally together with the other Guarantors, guarantees to each
Lender and the Administrative Agent, as provided in Article IV of the Credit
Agreement, the prompt payment and performance of the Obligations in full when
due (whether at stated maturity, as a mandatory prepayment, by acceleration or
otherwise) strictly in accordance with the terms thereof.

            2. The Subsidiary hereby acknowledges, agrees and confirms that, by
its execution of this Agreement, the Subsidiary will be deemed to be a party to
the Security Agreement and shall have all the obligations of an "Obligor" (as
such term is defined in the Security Agreement) thereunder as if it had executed
the Security Agreement. The Subsidiary hereby ratifies, as of the date hereof,
and agrees to be bound by, all of the terms, provisions and conditions contained
in the Security Agreement. Without limiting the generality of the foregoing
terms of this paragraph 2, the Subsidiary hereby grants to the Administrative
Agent, for the benefit of the Lenders, a continuing security interest in, and a
right of set off against, any and all right, title and interest of the
Subsidiary in and to the Collateral (as such term is defined in Section 2 of the
Security Agreement) of the Subsidiary. The Subsidiary hereby represents and
warrants to the Agent that:

            (i) The Subsidiary's chief executive office and chief place of
      business are (and for the prior four months have been) located at the
      locations set forth on Schedule 1 attached hereto and the Subsidiary keeps
      its books and records at such locations.

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            (ii) The type of Collateral owned by the Subsidiary and the location
      of all Collateral owned by the Subsidiary is as shown on Schedule 2
      attached hereto.

            (iii) The Subsidiary's legal name is as shown in this Agreement and
      the Subsidiary has not in the past four months changed its name, been
      party to a merger, consolidation or other change in structure or used any
      tradename except as set forth in Schedule 3 attached hereto.

            (iv) The patents and trademarks listed on Schedule 4 attached hereto
      constitute all of the registrations and applications for the patents and
      trademarks owned by the Subsidiary.

            (v) The Subsidiary Equity (as such term is defined in Section 1 of
      the Security Agreement) owned by the Subsidiary is listed on Schedule 5
      attached hereto.

            3. The address of the Subsidiary for purposes of all notices and
other communications is 117 Seaboard Lane, Building E, Franklin, TN 37067,
Attention of President or General Counsel of IASIS Healthcare Corporation
(Facsimile No. 615-846-3006).

            4. The Subsidiary hereby waives acceptance by the Administrative
Agent and the Lenders of the guaranty by the Subsidiary under Section 4 of the
Credit Agreement upon the execution of this Agreement by the Subsidiary.

            5. This Agreement may be executed in two or more counterparts, each
of which shall constitute an original but all of which when taken together shall
constitute one contract.

            6. This Agreement shall be governed by and construed and interpreted
in accordance with the laws of the State of New York.

                            [SIGNATURES ON NEXT PAGE]

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            IN WITNESS WHEREOF, the Subsidiary has caused this Joinder Agreement
to be duly executed by its authorized officers, and the Administrative Agent,
for the benefit of the Lenders, has caused the same to be accepted by its
authorized officer, as of the day and year first above written.

                             MOUNTAIN VISTA MEDICAL CENTER, LP

                             By: IASIS Healthcare Holdings, Inc.,
                                 its general partner

                             By:  /s/ Frank A. Coyle
                                 -----------------------------------------
                             Name:  Frank A. Coyle
                             Title: Secretary

                             Acknowledged and accepted:

                             BANK OF AMERICA, N.A.,
                             as Administrative Agent

                             By:  /s/ Kevin Wagley
                                 -----------------------------------------
                             Name:  Kevin Wagley
                             Title: Senior Vice President

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                                   SCHEDULE 1
               CHIEF EXECUTIVE OFFICE AND CHIEF PLACE OF BUSINESS

                          117 Seaboard Lane, Building E
                               Franklin, TN 37067

                                   SCHEDULE 2
                        TYPES AND LOCATIONS OF COLLATERAL

      None of the Collateral of the Subsidiary consists of, or is Proceeds of,
As-Extracted Collateral, Consumer Goods, Farm Products, Manufactured Homes or
Standing Timber. All Collateral of the Subsidiary is or will be located at (1)
the Subsidiary's chief executive office and chief place of business as set forth
on Schedule 1, and/or (2) the real property in Mesa, Maricopa County, Arizona,
conveyed to the Subsidiary by deed from VJ Crismon, LLC, recorded on November 5,
2004 as Instrument No. 20041303386 in the Official Records of the Maricopa
County Recorder and re-recorded on November 5, 2004 as Instrument No.
20041305290 in the Official Records of the Maricopa County Recorder.

                                   SCHEDULE 3
                                   TRADENAMES

                        Mountain Vista Medical Center, LP

                                   SCHEDULE 4
                             PATENTS AND TRADEMARKS

                                      None.

                                   SCHEDULE 5
                                SUBSIDIARY EQUITY

                                      None.