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                                                                    EXHIBIT 4.2

                             SUPPLEMENTAL INDENTURE

          SUPPLEMENTAL INDENTURE (this "Supplemental Indenture") dated as of
October 25, 1999, among IASIS Healthcare Corporation, a Delaware corporation
(the "Company"), the Guarantors named in the Indenture referred to below,
Biltmore Surgery Center, Inc., an Arizona Corporation, a subsidiary of the
Company (or its successor) (the "Guaranteeing Subsidiary") and The Bank of New
York, a New York banking corporation, as trustee under the Indenture referred to
below (the "Trustee").

                               W I T N E S S E T H

          WHEREAS, the Company has heretofore executed and delivered to the
Trustee an indenture, dated as of October 15, 1999, providing for the issuance
of an aggregate principal amount at maturity of $230,000,000 of 13% Senior
Subordinated Notes due 2009 (the "Notes");

          WHEREAS, the Indenture provides that under certain circumstances the
Guaranteeing Subsidiary shall execute and deliver to the Trustee a supplemental
indenture pursuant to which the Guaranteeing Subsidiary shall unconditionally
guarantee all of the Company's Obligations under the Notes and the Indenture on
the terms and conditions set forth herein (the "Subsidiary Guarantee"); and

          WHEREAS, pursuant to Section 9.01 of the Indenture, the Trustee is
authorized to execute and deliver this Supplemental Indenture.

          NOW THEREFORE, in consideration of the foregoing and for other good
and valuable consideration, the receipt of which is hereby acknowledged, the
Guaranteeing Subsidiary and the Trustee mutually covenant and agree for the
equal and ratable benefit of the Holders of the Notes as follows:

          1.        Capitalized Terms. Capitalized terms used herein without
definition shall have the meanings assigned to them in the Indenture.

          2.        Agreement to Guarantee. The Guaranteeing Subsidiary hereby
agrees as follows:




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          a.        Along with all Guarantors named in the Indenture, to jointly
                    and severally guarantee to each Holder of a Note
                    authenticated and delivered by the Trustee and to the
                    Trustee and its successors and assigns, irrespective of the
                    validity and enforceability of the Indenture, the Notes or
                    the obligations of the Company hereunder or thereunder,
                    that:

                    i.        the principal of and interest on the Notes will be
                              promptly paid in full when due, whether at
                              maturity, by acceleration, redemption or
                              otherwise, and interest on the overdue principal
                              of and interest on the Notes, if any, if lawful,
                              and all other obligations of the Company to the
                              Holders or the Trustee hereunder or thereunder
                              will be promptly paid in full or performed, all in
                              accordance with the terms hereof and thereof; and

                    ii.       in case of any extension of time of payment or
                              renewal of any Notes or any of such other
                              obligations, that same will be promptly paid in
                              full when due or performed in accordance with the
                              terms of the extension or renewal, whether at
                              stated maturity, by acceleration or otherwise.
                              Failing payment when due of any amount so
                              guaranteed or any performance so guaranteed for
                              whatever reason, the Guarantors shall be jointly
                              and severally obligated to pay the same
                              immediately.

          b.        The obligations hereunder shall be unconditional,
                    irrespective of the validity, regularity or enforceability
                    of the Notes or the Indenture, the absence of any action to
                    enforce the same, any waiver or consent by any Holder of the
                    Notes with respect to any provisions hereof or thereof, the
                    recovery of any judgment against the Company, any action to
                    enforce the same or any other circumstance which might
                    otherwise constitute a legal or equitable discharge or
                    defense of a Guarantor.

          c.        The following is hereby waived: diligence presentment,
                    demand of payment, filing of claims with a court in the
                    event of insolvency or bankruptcy of the Company, any right
                    to



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                    require a proceeding first against the Company, protest,
                    notice and all demands whatsoever.

          d.        This Subsidiary Guarantee shall not be discharged except by
                    complete performance of the obligations contained in the
                    Notes and the Indenture.

          e.        If any Holder or the Trustee is required by any court or
                    otherwise to return to the Company, the Guarantors, or any
                    Custodian, Trustee, liquidator or other similar official
                    acting in relation to either the Company or the Guarantors,
                    any amount paid by either to the Trustee or such Holder,
                    this Subsidiary Guarantee, to the extent theretofore
                    discharged, shall be reinstated in full force and effect.

          f.        The Guaranteeing Subsidiary shall not be entitled to any
                    right of subrogation in relation to the Holders in respect
                    of any obligations guaranteed hereby until payment in full
                    of all obligations guaranteed hereby.

          g.        As between the Guarantors, on the one hand, and the Holders
                    and the Trustee, on the other hand, (x) the maturity of the
                    obligations guaranteed hereby may be accelerated as provided
                    in Article 6 of the Indenture for the purposes of this
                    Subsidiary Guarantee, notwithstanding any stay, injunction
                    or other prohibition preventing such acceleration in respect
                    of the obligations guaranteed hereby, and (y) in the event
                    of any declaration of acceleration of such obligations as
                    provided in Article 6 of the Indenture, such obligations
                    (whether or not due and payable) shall forthwith become due
                    and payable by the Guarantors for the purpose of this
                    Subsidiary Guarantee.

          h.        The Guarantors shall have the right to seek contribution
                    from any non-paying Guarantor so long as the exercise of
                    such right does not impair the rights of the Holders under
                    the Guarantee.

          i.        The obligations hereunder shall be subject to the
                    subordination provisions of the Indenture.



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          3.        Execution and Delivery. Each Guaranteeing Subsidiary agrees
that the Subsidiary Guarantees shall remain in full force and effect
notwithstanding any failure to endorse on each Note a notation of such
Subsidiary Guarantee.

          4.        Guaranteeing Subsidiary May Consolidate, Etc. on Certain
Terms.

          a.        The Guaranteeing Subsidiary may not consolidate with or
                    merge with or into (whether or not such Guarantor is the
                    surviving Person) another corporation, Person or entity
                    whether or not affiliated with such Guarantor unless:

                    i.        subject to Section 11.05 of the Indenture, the
                              Person formed by or surviving any such
                              consolidation or merger (if other than a Guarantor
                              or the Company) unconditionally assumes all the
                              obligations of such Guarantor, pursuant to a
                              supplemental indenture in form and substance
                              reasonably satisfactory to the Trustee, under the
                              Notes, the Indenture and the Subsidiary Guarantee
                              on the terms set forth herein or therein; and

                    ii.       immediately after giving effect to such
                              transaction, no Default or Event of Default
                              exists.

          b.        In case of any such consolidation, merger, sale or
                    conveyance and upon the assumption by the successor
                    corporation, by supplemental indenture, executed and
                    delivered to the Trustee and satisfactory in form to the
                    Trustee, of the Subsidiary Guarantee endorsed upon the Notes
                    and the due and punctual performance of all of the covenants
                    and conditions of the Indenture to be performed by the
                    Guarantor, such successor corporation shall succeed to and
                    be substituted for the Guarantor with the same effect as if
                    it had been named herein as a Guarantor. Such successor
                    corporation thereupon may cause to be signed any or all of
                    the Subsidiary Guarantees to be endorsed upon all of the
                    Notes issuable hereunder which theretofore shall not have
                    been signed by the Company and delivered to the Trustee. All
                    the Subsidiary Guarantees so



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                    issued shall in all respects have the same legal rank and
                    benefit under the Indenture as the Subsidiary Guarantees
                    theretofore and thereafter issued in accordance with the
                    terms of the Indenture as though all of such Subsidiary
                    Guarantees had been issued at the date of the execution
                    hereof.

          c.        Except as set forth in Articles 4 and 5 of the Indenture,
                    and notwithstanding clauses (a) and (b) above, nothing
                    contained in the Indenture or in any of the Notes shall
                    prevent any consolidation or merger of a Guarantor with or
                    into the Company or another Guarantor, or shall prevent any
                    sale or conveyance of the property of a Guarantor as an
                    entirety or substantially as an entirety to the Company or
                    another Guarantor.

          5.        Releases.

          a.        In the event of a sale or other disposition of all of the
                    assets of any Guarantor, by way of merger, consolidation or
                    otherwise, or a sale or other disposition of all to the
                    capital stock of any Guarantor, then such Guarantor (in the
                    event of a sale or other disposition, by way of merger,
                    consolidation or otherwise, of all of the capital stock of
                    such Guarantor) or the corporation acquiring the property
                    (in the event of a sale or other disposition of all or
                    substantially all of the assets of such Guarantor) will be
                    released and relieved of any obligations under its
                    Subsidiary Guarantee; provided that the Net Proceeds of such
                    sale or other disposition are applied in accordance with the
                    applicable provisions of the Indenture, including without
                    limitation Section 4.10 of the Indenture. Upon delivery by
                    the Company to the Trustee of an Officers' Certificate and
                    an Opinion of Counsel to the effect that such sale or other
                    disposition was made by the Company in accordance with the
                    provisions of the Indenture, including without limitation
                    Section 4.10 of the Indenture, the Trustee shall execute any
                    documents reasonably required in order to evidence the
                    release of any Guarantor from its obligations under its
                    Subsidiary Guarantee.



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          b.        Any Guarantor not released from its obligations under its
                    Subsidiary Guarantee shall remain liable for the full amount
                    of principal of and interest on the Notes and for the other
                    obligations of any Guarantor under the Indenture as provided
                    in Article 11 of the Indenture or the Supplemental
                    Indenture.

          6.        No Recourse Against Others. No past, present or future
director, officer, employee, incorporator, stockholder or agent of the
Guaranteeing Subsidiary, as such, shall have any liability for any obligations
of the Company or any Guaranteeing Subsidiary under the Notes, any Subsidiary
Guarantees, the Indenture or this Supplemental Indenture or for any claim based
on, in respect of, or by reason of, such obligations or their creation. Each
Holder of the Notes by accepting a Note waives and releases all such liability.
The waiver and release are part of the consideration for issuance of the Notes.
Such waiver may not be effective to waive liabilities under the federal
securities laws and it is the view of the SEC that such a waiver is against
public policy.

          7.        NEW YORK LAW TO GOVERN. THE INTERNAL LAW OF THE STATE OF NEW
YORK SHALL GOVERN AND BE USED TO CONSTRUE THIS SUPPLEMENTAL INDENTURE BUT
WITHOUT GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT
THAT THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED
THEREBY.

          8.        Counterparts. The parties may sign any number of copies of
this Supplemental Indenture. Each signed copy shall be an original, but all of
them together represent the same agreement.

          9.        Effect of Headings. The Section headings herein are for
convenience only and shall not affect the construction hereof.

          10.       The Trustee. The Trustee shall not be responsible in any
manner whatsoever for or in respect of the validity or sufficiency of this
Supplemental Indenture or for or in respect of the recitals contained herein,
all of which recitals are made solely by the Guaranteeing Subsidiary and the
Company.



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     IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be duly executed and attested, all as of the date first above
written.

Dated: October 25, 1999

                        IASIS HEALTHCARE CORPORATION

                        By: /s/ Wayne Gower
                           ---------------------------------------------
                           Name:  C. Wayne Gower
                           Title: President and Chief Executive Officer

                        BAPTIST JOINT VENTURE HOLDINGS, INC.
                        BEAUMONT HOSPITAL HOLDINGS, INC.
                        BILTMORE SURGERY CENTER, INC.,
                        a Delaware Corporation
                        BILTMORE SURGERY CENTER, INC.,
                        an Arizona Corporation
                        CLINICARE OF UTAH, INC.
                        DAVIS HOSPITAL & MEDICAL CENTER, INC.
                        DAVIS SURGICAL CENTER HOLDINGS, INC.
                        FIRST CHOICE PHYSICIANS NETWORK HOLDINGS, INC.
                        HEALTH CHOICE ARIZONA, INC.
                        IASIS HEALTHCARE HOLDINGS, INC.
                        IASIS MANAGEMENT COMPANY
                        JORDAN VALLEY HOSPITAL, INC.
                        METRO AMBULATORY SURGERY CENTER, INC.
                        PIONEER VALLEY HEALTH PLAN, INC.
                        PIONEER VALLEY HOSPITAL, INC.
                        ROCKY MOUNTAIN MEDICAL CENTER, INC.
                        SALT LAKE REGIONAL MEDICAL CENTER, INC.
                        SANDY CITY HOLDINGS, INC.
                        SOUTHRIDGE PLAZA HOLDINGS, INC.
                        SSJ ST. PETERSBURG HOLDINGS, INC.

                        By: /s/ Wayne Gower
                           ---------------------------------------------
                           Name:  C. Wayne Gower
                           Title: President and Chief Executive Officer



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                        MEMORIAL HOSPITAL OF TAMPA, LP
                        MESA GENERAL HOSPITAL, LP
                        ODESSA REGIONAL HOSPITAL, LP
                        PALMS OF PASADENA HOSPITAL, LP
                        SOUTHWEST GENERAL HOSPITAL, LP
                        ST. LUKE'S MEDICAL CENTER, LP
                        ST. LUKE'S BEHAVIORAL HOSPITAL, LP
                        TEMPE ST. LUKE'S HOSPITAL, LP
                        TOWN & COUNTRY HOSPITAL, LP

                        By IASIS HEALTHCARE HOLDINGS, INC.

                        By: /s/ Wayne Gower
                           ---------------------------------------------
                           Name:  C. Wayne Gower
                           Title: President and Chief Executive Officer

                        THE BANK OF NEW YORK,
                             as Trustee

                        By: /s/ Robert A.Massimillo
                           ---------------------------------------------
                           Name:  Robert A. Massimillo
                           Title: Assistant Vice President