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                                                                   Exhibit 10.72




                                  SYMBION, INC.

                 EXECUTIVE CHANGE IN CONTROL SEVERANCE PLAN AND

                            SUMMARY PLAN DESCRIPTION




















                       ADOPTED EFFECTIVE DECEMBER 11, 1997
             (REVISED EFFECTIVE MAY 11, 2000 TO REFLECT NAME CHANGE)


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                                  SYMBION, INC.
                 EXECUTIVE CHANGE IN CONTROL SEVERANCE PLAN AND
                            SUMMARY PLAN DESCRIPTION


                                TABLE OF CONTENTS



INTRODUCTION   Introduction....................................................1

SECTION  1.    In General......................................................1

SECTION  2.    Definitions.....................................................1

SECTION  3.    What Benefits Are Provided Under the Plan?......................6

SECTION  4.    How Do I Become Eligible to Receive Benefits?...................6

SECTION  5.    How Do I Make a Claim for Benefits?.............................7

SECTION  6.    Can I Lose My Plan Benefits?....................................7

SECTION  7.    What Are My Rights if My Claim for Benefits Is Denied?..........7

SECTION  8.    May I Assign My Rights Under This Plan?.........................8

SECTION  9.    What Events Can Cause the Plan To Be Changed or Terminated?.....9

SECTION  10.   Additional Information..........................................9

SECTION  11.   What Are My Rights Under ERISA?................................10

SECTION  12.   Summary of Plan Information....................................12



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INTRODUCTION

This Plan document was adopted effective December 11, 1997, and revised
effective May 11, 2000 to reflect that UniPhy Healthcare, Inc. changed its name
to Symbion, Inc., and is a summary of your benefits, rights and obligations
under the Symbion, Inc. Executive Change in Control Severance Plan (the "Plan").
This document is intended to comply with both the summary plan description and
the written plan requirements of the Employee Retirement Income Security Act of
1974 ("ERISA") and the regulations issued under ERISA by the United States
Department of Labor.

Symbion, Inc. ("Symbion") may generally amend or terminate the Plan at any time
prior to a "change in control" (see definitions). For that reason, all
statements in this document are subject to change at any time prior to a change
in control without notice.

The Plan Administrator has the discretion to interpret the provisions of the
Plan and make determinations for the payment of Plan benefits. All such
determinations are final, binding and conclusive.


SECTION 1. IN GENERAL

Symbion has established the Plan with the intention of providing benefits to
Eligible Employees of Symbion and its Affiliates under the conditions described
in this document. Plan benefits are intended to provide additional compensation
to Eligible Employees whose positions are eliminated or adversely effected
following a change in control of Symbion. Therefore, the amount of your benefit
is calculated without regard to your actual period of unemployment following a
change in control, if any.

This document constitutes the entire written Plan. Any oral or other written
expressions of the Plan or related to the Plan or its subject matter are
completely superseded by this document. Except for a formal written Plan
amendment that is properly adopted by Symbion, or a written modification
authorized under Section 9, any oral or written statements concerning the Plan
shall not modify or add to this Plan document.

As is more fully explained in Section 4, severance benefits are not provided
under this Plan if your employment termination is not connected with a Change in
Control.

SECTION 2. DEFINITIONS

Defined terms in the Plan are indicated by initial capitalization of the term.
References to a "Section" mean a section of this Plan. Pronouns that refer to
one



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gender include the other gender. "You" or "your" means you, an individual in the
employ of Symbion.

     a.   "Administrator" or "Plan Administrator" means the chief executive
officer of Symbion. The Administrator may delegate any of his or her duties or
authorities to a committee of the Board of Directors. The Administrator has
absolute discretion to make all decisions under the Plan, including making
determinations about eligibility for and the amounts of Benefits payable under
the Plan and interpreting all Plan provisions. All decisions of the
Administrator are final, binding and conclusive. If a Change in Control occurs,
as described in Section 2.e, the Administrator shall be the individual who was
the chief executive officer of Symbion immediately prior to the Change in
Control.

     b.   "Affiliate" means Symbion and all corporations, partnerships, trusts
and other entities that are members, with Symbion, of a controlled group of
corporations or a group of trades or businesses under common control under
Sections 414(b) and (c) of the Internal Revenue Code.

     c.   "Annual Pay" means the following items of compensation payable to an
Eligible Employee immediately prior to the time of a Change in Control that
gives rise to payment of Benefits to the Eligible Employee hereunder:

          (1)  Normal monthly salary payable on regular payroll dates, as
               adjusted to an annualized rate.

          (2)  Cash bonuses (including deferred bonus accruals) normally payable
               in the fiscal year of Symbion that includes the Change in
               Control, calculated by reference to (i) the bonus amount that has
               been determined for the fiscal year, (ii) if no bonus amount has
               been determined, the bonus payment plan or policy previously
               adopted by the board of directors of Symbion, or, (ii) if no such
               plan or policy has been adopted, the amount of bonuses paid in
               the prior fiscal year (as adjusted for increases in cost of
               living announced by federal government) to the Eligible Employee
               or to a similarly situated employee of Symbion or an Affiliate,
               and as enhanced for increases in the profitability of Symbion or
               increases in value of shareholder equity.

          (3)  The value of noncash benefits (taxable or nontaxable) under
               fringe benefit arrangements of Symbion or an Affiliate normally
               available to the Eligible Employee, to the extent that such
               fringe benefits are not otherwise provided to the Eligible
               Employee as a Benefit pursuant to Section 4

     d.   "Benefit" means the severance benefits described in Section 3.



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     e.   "Change in Control" means the occurrence at any time during the
employment term of an Eligible Employee of any of the following events:

          (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-Control
               Acquisition" shall mean an acquisition by (1) 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"), (2) the
               Company or its Subsidiaries, or (3) 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 Company's Board of Directors (the "Incumbent
               Board"), cease for any reason to constitute at least a majority
               of the members of the Company's Board of Directors; provided,
               however, that if the election, or nomination for election by the
               Company's stockholders, 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
               14a-11 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 Company's Board of Directors (a "Proxy
               Contest") including by reason of any agreement intended to avoid
               or settle any Election Contest or Proxy Contest; or

          (3)  Approval by stockholders of the Company of:



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               (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 stockholders 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 corporation
                         resulting from such merger or consolidation or
                         reorganization (the "Surviving Corporation") 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
                         Corporation, or a corporation beneficially directly or
                         indirectly owning a majority of the Voting Securities
                         of the Surviving Corporation;

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

              (iii) An agreement for the sale or other disposition of all of
                    the assets of the Company to any Person (other than a
                    transfer to a Subsidiary).

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


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Voting Securities Beneficially Owned by the Subject Person, then a Change in
Control shall occur.

     f.   "Eligible Employee" means an Employee who satisfies the eligibility
requirements of Section 4 and is identified on Exhibit A to this Plan as an
Eligible Employee.

     g.   "Employee" means an employee of Symbion or an Affiliate.

     h.   "ERISA" means the Employee Retirement Income Security Act of 1974, as
          amended.

     i.   "Plan" means the Symbion, Inc. Executive Change in Control Severance
          Plan.

     j.   "Successor Employer" means a person or entity that acquires all or any
part of Symbion through purchase of assets, purchase of stock, trade of assets
or stock, spin-off, merger or acquisition in a transaction that is a Change in
Control, or a person or entity that acquires control of Symbion in any similar
type of transaction.

     k.   "Symbion" means Symbion, Inc., and its successors and assigns.



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SECTION 3. WHAT BENEFITS ARE PROVIDED UNDER THE PLAN?

Amount of Benefits:

Only Eligible Employees who satisfy the conditions of Section 4 will be entitled
to Benefits. The amount of Benefits shall be:

     a.   Cash compensation equal to the Eligible Employee's Annual Pay or
          one-half of the Eligible Employee's Annual Pay, as set forth on
          Exhibit A.

     b.   Participation in medical, life, disability and similar benefit plans
          that are offered to active employees of Symbion, or its successor, for
          a period of 6 or 12 months, as set forth on Exhibit A, following
          termination of employment at no cost to the Eligible Employee.

Schedule of Payments:

Symbion will pay cash Benefits in a single lump sum within 30 days following
termination of employment of an Eligible Employee or over 6 or 12 months, as
determined by the Plan Administrator. All other amounts will be promptly paid
upon submission of receipts or other evidence of expenses eligible for
reimbursement as Benefits to the chief financial officer of Symbion or his
designee.

SECTION 4. HOW DO I BECOME ELIGIBLE TO RECEIVE BENEFITS?

You will become entitled to Benefits under the Plan if you are an Eligible
Employee and satisfy the following conditions:

     a.   Your employment is terminated in connection with a Change in Control.

     b.   You are not offered employment by Symbion or a Successor Employer that
          is substantially equivalent to or better than the position you held
          with Symbion immediately prior to the Change in Control and the
          position is not maintained for at least 12 months. The determination
          of "substantially equivalent" shall be made by the Plan Administrator
          on the basis of all relevant facts and circumstances, including
          compensation, retirement and welfare benefits, fringe benefits, level
          of responsibility, the similarity of duties and responsibilities as
          compared to the Eligible Employee's work training and experience, and
          the amount of time reasonably required to perform the duties of the
          position. A position is not substantially equivalent unless: (i) the
          cash compensation offered is the same or higher than you earned
          immediately prior to the Change in Control, as adjusted for annual


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          cost of living increases; (ii) deferred compensation, incentive and
          equity compensation, and health and welfare benefits are not, in the
          aggregate similar, to those provided immediately prior to the Change
          in Control; or (iii) the workplace to be provided is more than 50
          miles from the workplace inhabited by the Eligible Employee
          immediately prior to the Change in Control.

Determinations of eligibility for Benefits are made by the Administrator. Any
decisions as to eligibility, the availability of Benefits under the Plan or the
interpretation of the Plan's provisions shall be made by the Administrator in
its sole and absolute discretion. Such decisions shall be final, binding and
conclusive.

SECTION 5. HOW DO I MAKE A CLAIM FOR BENEFITS?

If your Benefits are not automatically paid to you, you may file a request for
Benefits in writing with the Plan Administrator and a copy to the chief
executive officer.

SECTION 6. CAN I LOSE MY PLAN BENEFITS?

Generally, you will not be entitled to Plan Benefits if you do not satisfy the
eligibility requirements and conditions stated in Section 4. Failure to timely
submit an application for benefits in writing, as specified in Section 5, will
result in a loss of Plan Benefits.

You cannot lose your Benefits if following termination of employment you become
employed by Symbion or an Affiliate after Benefits are paid.

SECTION 7. WHAT ARE MY RIGHTS IF MY CLAIM FOR BENEFITS IS DENIED?

If an Employee's claim for Benefits is denied, the Administrator will furnish
written notice of denial to the Employee making the claim (the "Claimant")
within 90 days of the date the claim is received, unless special circumstances
require an extension of time for processing the claim. This extension will not
exceed 90 days, and the Claimant must receive written notice stating the grounds
for the extension and the length of the extension within the initial 90-day
review period. If the Administrator does not provide written notice, the
Claimant may deem the claim denied and seek review according to the appeals
procedures set forth below.

The notice of denial to the Claimant shall state:

     a.   the specific reasons for the denial,


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     b.   specific references to pertinent provisions of the Plan on which the
          denial was based,

     c.   a description of any additional material or information needed for the
          Claimant to perfect his or her claim and an explanation of why the
          material or information is needed, and

     d.   a statement that the Claimant may request a review upon written
          application to the Administrator, review pertinent Plan documents, and
          submit issues and comments in writing and that any appeal that the
          Claimant wishes to make of the adverse determination must be in
          writing to the Administrator within 60 days after the Claimant
          receives notice of denial of benefits.

The notice of denial of benefits shall identify the name and address of the
Administrator to which the Claimant may forward an appeal. The notice may state
that failure to appeal the action to the Administrator in writing within the
60-day period will render the determination final, binding and conclusive.

If the Claimant appeals to the Administrator, the Claimant or his or her
authorized representative may submit in writing whatever issues and comments he
or she believes to be pertinent. The Administrator shall reexamine all facts
related to the appeal and make a final determination of whether the denial of
benefits is justified under the circumstances. The Administrator shall advise
the Claimant in writing of:

     a.   the Administrator's decision on appeal,

     b.   the specific reasons for the decision, and

     c.   the specific provisions of the Plan on which the decision is based.

Notice of the Administrator's decision shall be given within 60 days of the
Claimant's written request for review, unless additional time is required due to
special circumstances. In no event shall the Administrator render a decision on
an appeal later than 120 days after receiving a request for a review.

SECTION 8. MAY I ASSIGN MY RIGHTS UNDER THIS PLAN?

No. Any attempt to assign rights under the Plan is invalid and void.

SECTION 9. WHAT EVENTS CAN CAUSE THE PLAN TO BE CHANGED OR TERMINATED?



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Symbion may terminate or amend the Plan at any time prior to a Change in Control
in its sole discretion. However, once a Change in Control occurs, no amendment
or termination will be effective with respect to an Eligible Employee unless he
or she consents to such amendment in writing after consultation with legal
counsel.

In compliance with Section 402(b)(3) of ERISA, Symbion must comply with the
following procedure before any termination or amendment to the Plan is
effective:

     a.   The Plan may only be modified or terminated by a written amendment
          that is authorized by Symbion.

     b.   Symbion's authorization of the amendment must be evidenced by one of
          the following: (1) a resolution of the board of directors; (2)
          execution of the amendment by the chief executive officer, president
          or secretary; or (3) ratification of the amendment by either a
          resolution of the board of directors or written confirmation of
          ratification by the chief executive officer, president or secretary.

     c.   Notice of the amendment must be provided to the Administrator.

     d.   Notice of the amendment must be provided to all Eligible Employees at
          least 30 days prior to the effective date of the amendment.

Oral amendments and modifications of this Plan are not effective. All amendments
and modifications must be in writing and signed as provided above to be
effective.

SECTION 10. ADDITIONAL INFORMATION

These Benefits are paid out of the general assets of Symbion. No particular fund
or trust has been established to pay these Benefits, and this Plan does not give
you any rights to any particular assets of Symbion.

Cash amounts paid under a severance plan is generally considered taxable income
to the recipient.

SECTION 11. WHAT ARE MY RIGHTS UNDER ERISA?

As a participant in the Plan, you are entitled to certain rights and protections
under ERISA. ERISA provides that all Plan participants shall be entitled to:

     a.   Examine, without charge, at the Plan Administrator's office and at
          other specified locations, all Plan documents, including insurance
          contracts, and copies of all documents filed by the Plan with the U.S.


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          Department of Labor, such as detailed annual reports and plan
          descriptions.

     b.   Obtain copies of all Plan documents and other Plan information upon
          written request to the Plan Administrator. The Plan Administrator may
          make a reasonable charge for the copies.

     c.   Receive a summary of the Plan's annual financial report. The Plan
          Administrator is required by law to furnish each participant with a
          copy of this summary annual report.

In addition to creating rights for Plan participants, ERISA imposes duties upon
the people who are responsible for the operation of the employee benefit Plan.

The people who operate your Plan, called "fiduciaries" of the Plan, have a duty
to do so prudently and in the interest of you and other Plan participants and
beneficiaries.

No one, including Symbion or any other person, may fire you or otherwise
discriminate against you in any way to prevent you from obtaining a benefit
under this Plan or from exercising your rights under ERISA.

If a claim for a Benefit is denied in whole or in part, you must receive a
written explanation of the reason for the denial. You have the right to have the
Plan Administrator review and reconsider your claim.

Under ERISA, there are steps you can take to enforce the above rights. For
instance, if you request materials from the Plan and do not receive them within
30 days, you may file suit in a federal court. In such a case, the court may
require the Plan Administrator to provide the materials and pay you up to $100 a
day until you receive the materials, unless the materials were not sent because
of reasons beyond the control of the Administrator.

If you have a claim for benefits that is denied or ignored, in whole or in part,
you may file suit in a state or federal court. If it should happen that Plan
fiduciaries misuse the Plan's money or if you are discriminated against for
asserting your rights, you may seek assistance from the U.S. Department of Labor
or you may file suit in a federal court. The court will decide who should pay
court costs and fees. If you lose, the court may order you to pay these costs
and fees, for example, if it finds your claim is frivolous.

If you have any questions about your Plan, you should contact the Plan
Administrator.



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          If you have any questions about this statement or about your rights
          under ERISA, you should contact the nearest Area Office of the U.S.
          Labor-Management Services Administration, Department of Labor.



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SECTION 12. SUMMARY OF PLAN INFORMATION

Name of Plan:   Symbion, Inc. Executive Change in Control Severance Plan

Name and Address of Company:

                Symbion, Inc.
                3401 West End Avenue
                Suite 760
                Nashville, Tennessee 37203

Who Pays for the Plan: The cost of the Plan is paid entirely by Symbion.

Company's Employer Identification No.: 62-1625480

Plan Year: January 1 to December 31

Plan Administrator, Name, Address and Telephone No.:

                Chief Executive Officer
                Symbion, Inc.
                3401 West End Avenue
                Suite 760
                Nashville, Tennessee 37203

Agent for Service of Legal Process on the Plan: Chief executive officer or the
                                                Plan Administrator.

     IN WITNESS WHEREOF, Symbion, Inc., acting through the undersigned
authorized representative, has executed this Plan as of the day and year written
above.


                                  SYMBION, INC.



                                  By: /s/ Richard E. Francis, Jr.
                                     -------------------------------------------

                                  Its: CEO
                                      ------------------------------------------

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