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                                                                    EXHIBIT 4.10

                          REGISTRATION RIGHTS AGREEMENT

      THIS REGISTRATION RIGHTS AGREEMENT (this "Agreement") is made as of July
1, 2005, between PSYCHIATRIC SOLUTIONS, INC., a Delaware corporation (the
"Company"), and ARDENT HEALTH SERVICES LLC, a Delaware limited liability company
(the "Holder").

      RECITAL:

      The Company and Holder are parties to that certain Amended and Restated
Stock Purchase Agreement dated as of June 30, 2005 (the "Purchase Agreement"),
which provides, among other things, that a portion of the purchase price shall
be paid to Holder in the form of common stock of the Company, par value $0.01
per share (the "Common Stock"). Capitalized terms used but not defined in this
Agreement have the meanings assigned to such terms in the Purchase Agreement. As
an inducement to Holder to enter into the Purchase Agreement, the Company agrees
with the Holder as follows:

      AGREEMENT:

      NOW, THEREFORE, the parties hereby agree as follows:

      1. CERTAIN DEFINITIONS. As used in this Agreement, the following terms
shall have the following respective meanings:

            1.1 AFFILIATES. "Affiliate" shall mean any person that, directly or
indirectly, through one or more intermediaries, controls or is controlled by, or
is under common control with, any party specified in this Agreement.

            1.2 COMMISSION. "Commission" shall mean the United States Securities
and Exchange Commission or any other federal agency at the time administering
the Securities Act.

            1.3 COMMON SHARES. "Common Shares" shall mean the shares of Common
Stock issued at any time to the Holder pursuant to the Purchase Agreement.

            1.4 EXCHANGE ACT. "Exchange Act" shall mean the Securities Exchange
Act of 1934, as amended, or any similar Federal statute, and the rules and
regulations of the Commission thereunder, all as the same shall be in effect
from time to time.

            1.5 PERSON. "Person" shall mean any individual, partnership, limited
liability company, corporation, trust or other entity.

            1.6 REGISTER; REGISTERED; REGISTRATION. "Register," "registered" and
"registration" shall refer to a registration effected by preparing and filing a
registration statement in compliance with the Securities Act, and the
declaration or ordering of the effectiveness of such registration statement by
the Commission.

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            1.7 REGISTRABLE SECURITIES. "Registrable Securities" shall mean (i)
the Common Shares and (ii) all shares of the Common Stock issued as a dividend
on, or other distribution with respect to, or in exchange or in replacement of,
the Common Shares, until, in the case of any such security, its effective
registration under the Securities Act and resale in accordance with the
registration statement covering it.

            1.8 REGISTRATION EXPENSES. "Registration Expenses" shall mean all
expenses incurred by the Company in complying with Section 2, including all
registration and filing fees, exchange listing fees, printing expenses, fees and
disbursements of counsel for the Company and reasonable fees and expenses for
counsel for Holder up to $15,000, state securities' law fees and expenses, the
expense of any special consents and advice or similar audit services of
independent auditors incident to or required by any such registration.

            1.9 SECURITIES ACT. "Securities Act" shall mean the Securities Act
of 1933, as amended, or any similar federal statute, and the rules and
regulations of the Commission thereunder, all as the same shall be in effect
from time to time.

      2. REGISTRATION RIGHTS

            2.1 SHELF REGISTRATION.

                  (a) The Company shall prepare and file with the Commission as
soon as practicable but in no event later than 30 days after the Closing Date, a
registration statement (the "Initial Shelf Registration Statement," and together
with any Subsequent Shelf Registration Statement (as defined below), including,
in each case, the prospectus, amendments and supplements to such registration
statements, including post-effective amendments, all exhibits, and all materials
incorporated by reference or deemed to be incorporated by reference in such
registration statements, are herein collectively referred to as the "Shelf
Registration Statement") for an offering to be made on a delayed or continuous
basis pursuant to Rule 415 of the Securities Act (the "Shelf Registration"),
registering the resale from time to time by Holder of all of the Registrable
Securities. The Initial Shelf Registration Statement shall be on Form S-3 or
other appropriate form under the Securities Act permitting registration of such
Registrable Securities for resale by Holder from time to time as set forth in
the Initial Shelf Registration Statement. The Company shall use its reasonable
best efforts to cause the Initial Shelf Registration Statement to be declared
effective under the Securities Act as promptly as is practicable, and in any
event within 90 days after the Closing Date, and to keep the Initial Shelf
Registration Statement (or any Subsequent Shelf Registration Statement)
continuously effective under the Securities Act to permit the prospectus
included therein to be lawfully delivered by Holder, for a period that will
terminate when all the Registrable Securities covered by the Shelf Registration
Statement have been sold pursuant thereto or pursuant to Rule 144 under the
Securities Act (such period, the "Effectiveness Period").

                  (b) If the Initial Shelf Registration Statement or any
Subsequent Shelf Registration Statement ceases to be effective for any reason at
any time during the Effectiveness Period (other than because all Registrable
Securities registered thereunder have been resold pursuant thereto or have
otherwise ceased to be Registrable Securities), the Company shall use its
reasonable best efforts to obtain the prompt withdrawal of any order suspending
the

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effectiveness thereof, and in any event shall within thirty (30) days of such
cessation of effectiveness amend such Shelf Registration Statement in a manner
reasonably expected to obtain the withdrawal of the order suspending the
effectiveness thereof, or file an additional registration statement in
connection with the Shelf Registration covering all of the securities that as of
the date of such filing are Registrable Securities (a "Subsequent Shelf
Registration Statement"). If a Subsequent Shelf Registration Statement is filed,
the Company shall use its reasonable best efforts to cause the Subsequent Shelf
Registration Statement to become effective as promptly as is practicable after
such filing and to keep such Subsequent Shelf Registration Statement
continuously effective until the end of the Effectiveness Period.

                  (c) The Company shall supplement and amend the Shelf
Registration Statement if required by the rules, regulations or instructions
applicable to the registration form used by the Company for such Shelf
Registration Statement, if required by the Securities Act.

                  (d) Notwithstanding any other provisions of this Agreement to
the contrary, the Company shall cause the Shelf Registration Statement and the
related prospectus and any amendment or supplement thereto, as of the effective
date of the Shelf Registration Statement, amendment or supplement, (i) to comply
in all material respects with the applicable requirements of the Securities Act
and the rules and regulations of the Commission and (ii) not to contain any
untrue statement of a material fact or omit to state a material fact required to
be stated therein or necessary in order to make the statements therein, in light
of the circumstances under which they were made, not misleading; provided,
however, that the Company shall not be responsible for untrue statements or
omissions arising from written information furnished to the Company by an
instrument duly executed by Holder and stated to be specifically for use in the
Shelf Registration Statement.

            2.2 REGISTRATION PROCEDURES. In connection with the Shelf
Registration contemplated by Section 2.1 hereof, the following provisions shall
apply:

                  (a) The Company shall furnish to Holder, prior to the filing
thereof with the Commission, a copy of any Shelf Registration Statement and each
amendment thereof and each supplement, if any, to the prospectus included
therein and the Company shall use its reasonable best efforts to reflect in the
Shelf Registration Statement, when so filed with the Commission, such comments
as the Holder may propose that are acceptable to the Company in its reasonable
discretion.

                  (b) The Company shall give written notice to the Holder (which
notice pursuant to clauses (ii) through (v) hereof shall be accompanied by an
instruction to suspend the use of the prospectus until the requisite changes
have been made):

                        (i) when the Shelf Registration Statement or any
amendment thereto has been filed with the Commission and when the Shelf
Registration Statement or any post-effective amendment thereto has become
effective;

                        (ii) of any request by the Commission for amendments or
supplements to the Shelf Registration Statement or the prospectus included
therein or for additional information;

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                        (iii) of the issuance by the Commission of any stop
order suspending the effectiveness of the Shelf Registration Statement or the
initiation of any proceedings for that purpose;

                        (iv) of the receipt by the Company or its legal counsel
of any notification with respect to the suspension of the qualification of the
Registrable Securities for sale in any jurisdiction or the initiation or
threatening of any proceeding for such purpose; and

                        (v) of the happening of any event that requires the
Company to file a post-effective amendment to the Shelf Registration Statement
or a supplement to the prospectus in order that the Shelf Registration Statement
or the prospectus do not contain an untrue statement of a material fact nor omit
to state a material fact required to be stated therein or necessary to make the
statements therein (in the case of the prospectus, in light of the circumstances
under which they were made) not misleading.

                  (c) The Company shall make every reasonable effort to obtain
the withdrawal, at the earliest possible time, of any order suspending the
effectiveness of the Shelf Registration Statement or the lifting of any
suspension of the qualification (or exemption from qualification) of any of the
Registrable Securities for sale in any jurisdiction in which they have been
qualified for sale.

                  (d) The Company shall furnish to Holder, without charge, at
least one copy of the Shelf Registration Statement and any post-effective
amendment thereto, including financial statements and schedules, if applicable,
and, if the Holder so requests in writing, all exhibits thereto (including
those, if any, incorporated by reference).

                  (e) The Company shall, during the Effectiveness Period,
deliver to Holder, without charge, as many copies of the prospectus (including
each preliminary prospectus, if any) included in the Shelf Registration
Statement and any amendment or supplement thereto as Holder may reasonably
request. The Company consents, subject to the provisions of this Agreement, to
the use of the prospectus or any amendment or supplement thereto by Holder in
connection with the offering and sale of the Registrable Securities covered by
the prospectus, or any amendment or supplement thereto, included in the Shelf
Registration Statement.

                  (f) Prior to any public offering of the Registrable Securities
pursuant to any Shelf Registration Statement, the Company shall register or
qualify or cooperate with the Holder and its counsel in connection with the
registration or qualification of the Registrable Securities for offer and sale
under the securities or "blue sky" laws of such states of the United States as
Holder reasonably requests in writing and do any and all other acts or things
reasonably necessary or advisable to enable the offer and sale in such
jurisdictions of the Registrable Securities covered by such Shelf Registration
Statement; provided, however, that in no event shall the Company be required to
qualify to do business as a foreign corporation in any jurisdiction where it
would not, but for the requirements of this paragraph (f), be required to be so
qualified, to subject itself to taxation in any such jurisdiction or to consent
to general service of process in any such jurisdiction.

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                  (g) The Company shall cooperate with Holder to facilitate the
timely preparation and delivery of certificates representing the Registrable
Securities to be sold pursuant to any Shelf Registration Statement and in such
denominations and registered in such names as Holder may request a reasonable
period of time prior to sales of the Registrable Securities pursuant to such
Shelf Registration Statement. The Company shall cause its counsel to promptly
issue any legal opinions that (i) are appropriate in the reasonable judgment of
such counsel and (ii) are requested by the Company's transfer agent in order to
process the sale of the Registrable Securities.

                  (h) Upon the occurrence of any event contemplated by
paragraphs (ii) through (v) of Section 2.2(b) above during the period for which
the Company is required to maintain an effective Shelf Registration Statement,
the Company shall promptly prepare and file a post-effective amendment to the
Shelf Registration Statement or a supplement to the related prospectus and any
other required document so that, as thereafter delivered to Holder or purchasers
of Registrable Securities, the prospectus will not contain an untrue statement
of a material fact or omit to state any material fact required to be stated
therein or necessary to make the statements therein, in light of the
circumstances under which they were made, not misleading. If the Company
notifies the Holder in accordance with paragraphs (ii) through (v) of Section
2.2(b) above to suspend the use of the prospectus until the requisite changes to
the prospectus have been made, then the Holder shall suspend use of such
prospectus and, if so directed by the Company, destroy or deliver to the Company
all copies then in Holder's possession of the prospectus covering such
Registrable Securities that was in effect at the time of such notice (such
period during which the availability of the Shelf Registration Statement and any
related prospectus is suspended being a "Deferral Period"). The Company will use
its reasonable best efforts to ensure that the use of the prospectus may be
resumed as promptly as is practicable. In all cases any Deferral Period will be
for the minimum period reasonably required for the Company to prepare and file
the necessary documents. The Company agrees that it shall not suspend trading
under the prospectus due to the occurrence of an event contemplated by Section
2.2(b)(v) unless the Company shall black-out trading for all of its officers and
members of its board of directors for the same period of time.

                  (i) The Company shall prepare and file with the Commission
such amendments and post-effective amendments to each Shelf Registration
Statement as may be necessary to keep such Shelf Registration Statement
continuously effective during the Effectiveness Period and shall cause the
related prospectus to be supplemented by any required prospectus supplement to
be filed pursuant to Rule 424 (or any similar provisions then in force) under
the Securities Act.

                  (j) The Company may require Holder to furnish to the Company
such information regarding the Holder and the distribution of the Registrable
Securities as the Company may from time to time reasonably require for inclusion
in the Shelf Registration Statement.

                  (k) The Company shall use its reasonable best efforts to take
all other steps necessary to effect the registration of the Registrable
Securities covered by a Shelf Registration Statement contemplated hereby.

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                  (l) The Company shall as promptly as practicable (if
reasonably requested by Holder) incorporate in a prospectus supplement or
post-effective amendment to the Shelf Registration Statement such information as
Holder shall, on the basis of an opinion of counsel experienced in such matters,
determine to be required to be included therein and make any required filings of
such prospectus supplement or such post-effective amendment; provided that the
Company shall not be required to take any actions under this Section 2.2(l) that
are not, in the reasonable opinion of counsel for the Company, in compliance
with applicable law.

                  (m) The Company shall cause all Registrable Securities covered
by the Shelf Registration Statement to be listed on the Nasdaq National Market.

            2.3 EXPENSES OF REGISTRATION. The Company shall pay all Registration
Expenses incurred in connection with the performance of the Company's
obligations under this Agreement.

      3. INDEMNIFICATION

            3.1 INDEMNIFICATION BY THE COMPANY. Except as limited by Section
3.3, the Company agrees to indemnify and hold harmless Holder and its
Affiliates, against all claims, losses, damages and liabilities, joint or
several (or actions in respect thereof, and including, but not limited to, any
claims, losses, damages, liabilities or actions relating to purchases and sales
of the Registrable Securities), including any of the foregoing incurred in
settlement of any litigation, commenced or threatened, to which any of them may
become subject under the Securities Act, the Exchange Act or other federal or
state law, arising out of or based on the following:

                  (a) any untrue statement or alleged untrue statement of a
material fact contained in the Shelf Registration Statement, or any omission or
alleged omission to state therein a material fact required to be stated therein
or necessary to make the statements therein not misleading in the light of the
circumstances under which they were made;

                  (b) any violation by the Company of any federal, state or
common law rule or regulation applicable to the Company in connection with the
Shelf Registration; and

                  (c) any legal and any other expenses reasonably incurred in
connection with investigating or defending any such claim, loss, damage,
liability or action, as incurred related to the foregoing.

            3.2 INDEMNIFICATION BY HOLDER. Holder shall indemnify the Company
and its Affiliates against all claims, losses, damages and liabilities, joint or
several (or actions in respect thereof), including any of the foregoing incurred
in settlement of any litigation, commenced or threatened, to which they may
become subject under the Securities Act or other federal or state law, arising
out of or based on:

                  (a) any untrue statement or alleged untrue statement of a
material fact contained in the Shelf Registration Statement, or any omission or
alleged omission to state therein a material fact required to be stated therein

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or necessary to make the statements therein not misleading in the light of the
circumstances under which they were made, in each case to the extent, but only
to the extent, that such untrue statement or alleged untrue statement or
omission or alleged omission is made in the Shelf Registration Statement in
reliance upon and in conformity with written information furnished to the
Company by an instrument duly executed by Holder and stated to be specifically
for use therein; and

                  (b) any legal and other expenses reasonably incurred in
connection with investigating or defending any such claim, loss, damage,
liability or action, as incurred related to the foregoing.

            3.3 LIMITATION ON THE INDEMNIFICATION OBLIGATION.

                  (a) No party required to provide indemnification under this
Section 3 (the "Indemnifying Party") shall be liable, and shall have any
indemnification obligation hereunder, for any amounts paid in settlement by any
party entitled to indemnification hereunder (the "Indemnified Party") of any
such loss, claim, damage, liability or action if such settlement is effected
without the consent of the Indemnifying Party (which consent shall not be
unreasonably withheld).

                  (b) The Company shall not be liable under Section 3.1 hereof
for any such claim, loss, damage, liability or expense to the extent it arises
out of or is based on any untrue statement or omission or alleged omission, made
in reliance on and in conformity with written information furnished to the
Company by an instrument duly executed by Holder and stated to be specifically
for use therein.

            3.4 INDEMNIFICATION PROCEDURE. Each Indemnified Party shall give
notice to the Indemnifying Party promptly after such Indemnified Party has
actual knowledge of any claim as to which indemnity may be sought, and shall
permit the Indemnifying Party to assume the defense of any such claim or any
litigation resulting therefrom, provided the Indemnifying Party acknowledges its
obligations to indemnify the Indemnified Party with respect to the claim and
provided further that counsel for the Indemnifying Party, who shall conduct the
defense of such claim or litigation, shall be approved by the Indemnified Party
(whose approval shall not unreasonably be withheld), and the Indemnified Party
may participate in such defense at such party's expense, and provided further
that the failure of any Indemnified Party to give notice as provided herein
shall not relieve the Indemnifying Party of its obligations under this Section 3
except to the extent that the failure to give such notice is materially
prejudicial to an Indemnifying Party's ability to defend such action and
provided further, that the Indemnifying Party shall not assume the defense for
matters as to which there is a conflict of interest or the Indemnified Party and
the Indemnifying Party can reasonably argue separate and different defenses;
however, the Indemnifying Party shall still bear the expense of the Indemnified
Party's defense. No Indemnifying Party, in the defense of any such claim or
litigation, shall, except with the consent of each Indemnified Party, consent to
entry of any judgment or enter into any settlement which does not include as an
unconditional term thereof the giving by the claimant or plaintiff to such
Indemnified Party of a release from all liability in respect to such claim or
litigation. If the Indemnifying Party does not assume the defense of any claim
or proceeding resulting therefrom, the Indemnified Party may defend against such
claim or proceeding as the

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Indemnified Party may deem appropriate and may settle such claim or proceeding
in such manner as the Indemnified Party may deem appropriate with the
Indemnifying Party's consent which shall not be unreasonably withheld, all
without prejudice to its right to indemnification hereunder.

            3.5 CONTRIBUTION, ALLOCATION, ETC. If the indemnification provided
for in this Section 3 is held by a court of competent jurisdiction to be
unavailable or insufficient to hold harmless an Indemnified Party in respect of
any losses, claims, damages or liabilities or actions in respect thereof
referred to therein, then each Indemnifying Party shall in lieu of indemnifying
such Indemnified Party contribute to the amount paid or payable by such
Indemnified Party as a result of such losses, claims, damages, liabilities or
actions in such proportion as appropriate to reflect the relative fault of the
Company, on the one hand, and Holder, on the other, in connection with the
statements or omissions which resulted in such losses, claims, damages,
liabilities or actions as well as any other relevant equitable considerations,
including the failure to give any notice under Section 4.4. The relative fault
shall be determined by reference to, among other things, whether the untrue or
alleged untrue statement of a material fact relates to information supplied by
the Company, on the one hand, or the Holder, on the other, and to the parties'
relative intent, knowledge, access to information and opportunity to correct or
prevent such statement or omission. The Company and Holder agree that it would
not be just and equitable if contributions pursuant to this paragraph where
determined by pro rata allocation or by any other method of allocation which did
not take account of the equitable considerations referred to above in this
paragraph. The amount paid or payable by an Indemnified Party as a result of the
losses, claims, damages, liabilities or action in respect thereof, referred to
above in this paragraph, shall be deemed to include any legal or other expenses
reasonably incurred by such Indemnified Party in connection with investigating
or defending any such action or claim. Notwithstanding the provisions of this
paragraph, Holder shall not be required to contribute any amount in excess of
the lesser of (i) the proceeds received by Holder for the sale of the
Registrable Securities covered by the Shelf Registration Statement and (ii) the
amount of any damages which it would have otherwise been required to pay by
reason of such untrue or alleged untrue statement or omission. No person guilty
of fraudulent misrepresentation shall be entitled to contribution from any
person who is not guilty of such fraudulent misrepresentation.

      4. MISCELLANEOUS PROVISIONS.

            4.1 TRANSFER OF REGISTRATION RIGHTS. The registration rights granted
under this Agreement may be assigned or otherwise conveyed by Holder, without
the consent of the Company and without the need for an express assignment, to
any Person in connection with the transfer of Registrable Securities to such
Person; provided however, that the Company is given written notice of such
transfer stating the name and address of the transferee or assignee and
identifying the Registrable Securities with respect to which such registration
rights are being transferred or assigned.

            4.2 GOVERNING LAW. This Agreement shall be governed by, and
construed and enforced in accordance with, the laws of the State of Delaware,
without giving effect to conflict of laws or any other rules or principles which
may require the application of the laws of any other jurisdiction.

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            4.3 DELAYS OR OMISSIONS. No delay or omission to exercise any right,
power or remedy accruing to Holder, upon any breach or default by the Company
under this Agreement, shall impair any such right, power or remedy of Holder nor
shall it be construed to be a waiver of any such breach or default, or an
acquiescence therein, or of or in any similar breach or default thereunder
occurring; nor shall any waiver of any single breach or default be deemed a
waiver of any other breach or default theretofore or thereafter occurring. Any
waiver, permit, consent or approval of any kind or character on the part of
Holder or any breach or default under this Agreement, or any waiver on the part
of Holder of any provisions or conditions of this Agreement, must be in writing
and shall be effective only to the extent specifically set forth in such
writing. All remedies, either under this Agreement, or by law or otherwise
afforded to Holder or the Company shall be cumulative and not alternative.

            4.4 RULE 144. The Company shall use its reasonable best efforts to
file the reports required to be filed by it under the Securities Act and the
Exchange Act in a timely manner and, if at any time, the Company is not required
to file such reports, it will, upon the request of Holder, make publicly
available other information so long as necessary to permit sales of their
securities pursuant to Rule 144 under the Securities Act. The Company covenants
that it will take such further action as Holder may reasonably request, all to
the extent required from time to time to enable Holder to sell Registrable
Securities without registration under the Securities Act within the limitation
of the exemptions provided by Rule 144. Upon the request of Holder, the Company
shall deliver to Holder a written statement as to whether it has complied with
such filing requirements.

            4.5 REMEDIES. Each of the parties hereto acknowledges and agrees
that any failure by a party to perform its obligations hereunder or otherwise
breach this Agreement would cause irreparable injury for which there is no
adequate remedy at law, that it will not be possible to measure damages for such
injuries precisely and that, in the event of any such failure, a party may
obtain such relief as may be required to specifically enforce the other party's
obligations hereunder. The parties further agree to waive the defense in any
action for specific performance that a remedy at law would be adequate.

            4.6 NO INCONSISTENT AGREEMENTS. The Company will not on or after the
date of this Agreement enter into any agreement with respect to its securities
that is inconsistent with the rights granted to Holder in this Agreement or
otherwise conflicts with the provisions hereof. The Company represents and
warrants that the rights granted to Holder hereunder do not in any way conflict
with and are not inconsistent with the rights granted to the holders of
securities of the Company under any agreement in effect on the date hereof.

            4.7 ENTIRE AGREEMENT. This Agreement constitutes the entire
agreement and understanding of the parties hereto with respect to the subject
matter hereof, and supersedes all prior agreements, correspondence, arrangements
and understandings relating to the subject matter hereof.

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            4.8 BINDING EFFECT. All of the terms, provisions and conditions
hereof shall be binding upon and shall inure to the benefit of and be
enforceable by the parties hereto, and their respective heirs, personal
representatives, successors and assigns.

            4.9 HEADINGS; CONSTRUCTION. The headings contained herein are for
the purposes of convenience only, and will not be deemed to constitute a part of
this Agreement or to affect the meaning or interpretation of this Agreement in
any way. Unless the context clearly states otherwise, the use of the singular or
plural in this Agreement shall include the other and the use of any gender shall
include all others. The parties have participated jointly in the negotiation and
drafting of this Agreement. If any ambiguity or question of intent or
interpretation arises, no presumption or burden of proof shall arise favoring or
disfavoring any party by virtue of the authorship of any of the provisions of
this Agreement. All references herein to Sections shall refer to this Agreement
unless the context clearly otherwise requires.

            4.10 NOTICES. All notices and other communications hereunder shall
be in writing and shall be deemed given upon (a) transmitter's confirmation of
receipt of a facsimile transmission, (b) confirmed delivery by a standard
overnight carrier or when delivered by hand or (c) the expiration of five (5)
business days (or seven (7) business days where the addressee is not in the
United States) after the day when mailed by certified or registered mail,
postage prepaid, to the addresses set forth in the Purchase Agreement or to such
other address as any party may, from time to time, designate in a written notice
given in a like manner.

            4.11 SEVERABILITY OF PROVISIONS. If a court in any proceeding holds
any provision of this Agreement or its application to any person or circumstance
invalid, illegal or unenforceable, the remainder of this Agreement, or the
application of such provision to persons or circumstances other than those to
which it was held to be invalid, illegal or unenforceable, shall not be
affected, and shall be valid, legal and enforceable to the fullest extent
permitted by law, but only if and to the extent such enforcement would not
materially and adversely frustrate the parties' essential objectives as
expressed in this Agreement. Furthermore, in lieu of any such invalid or
unenforceable term or provision, the parties intend that the court add to this
Agreement a provision as similar in terms to such invalid or unenforceable
provision as may be valid and enforceable, so as to effect the original intent
of the parties to the greatest extent possible.

            4.12 THIRD PARTY BENEFICIARIES. This Agreement does not create, and
will not be construed as creating, any rights enforceable by any person not a
party to this Agreement.

            4.13 AMENDMENT. This Agreement may be amended, modified, superseded,
or canceled only by a written instrument signed by all of the parties hereto and
any of the terms, provisions and conditions hereof may be waived, only by a
written instrument signed by the waiving party.

            4.14 COUNTERPARTS; FACSIMILE SIGNATURES. This Agreement may be
executed in any number of counterparts and each such counterpart shall for al
purposes be deemed to be an original, and all such counterparts shall together
constitute but one and the same instrument. Facsimile signatures on this
Agreement shall be deemed to be original signatures for all purposes.

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      IN WITNESS WHEREOF, the parties have entered into this Agreement as of the
date first written above.

                                  PSYCHIATRIC SOLUTIONS, INC.

                                  By: /s/ Joey A. Jacobs
                                      ----------------------------------
                                  Name: Joey A. Jacobs
                                  Title: President and Chief Executive Officer

                                  ARDENT HEALTH SERVICES LLC

                                  By: /s/ Stephen C. Petrovich
                                      -----------------------------------
                                  Name: Stephen C. Petrovich
                                  Title: Senior Vice President

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