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                                                                   EXHIBIT 10.66



                              AMENDED AND RESTATED
                        AMBULATORY RESOURCE CENTRES, INC.
                             1997 STOCK OPTION PLAN

1.       Purpose; Types of Awards; Construction.

         The purpose of the Ambulatory Resource Centres, Inc. 1997 Stock Option
Plan (the "Plan") is to afford an incentive to executive officers, other key
employees, directors and consultants of Ambulatory Resource Centres, Inc. (the
"Company"), or any subsidiary of the Company which now exists or hereafter is
organized or acquired by the Company, to acquire a proprietary interest in the
Company, to continue as employees, directors or consultants, to increase their
efforts on behalf of the Company and to promote the success of the Company's
business. The provisions of the Plan are intended to satisfy the requirements of
Section 16(b) of the Securities Exchange Act of 1934, and shall be interpreted
in a manner consistent with the requirements thereof, as now or hereafter
construed, interpreted and applied by regulations, rulings and cases.

2.       Definitions.

         As used in this Plan, the following words and phrases shall have the
meanings indicated:

         (a)   "Acceleration Date" shall have the meaning set forth in
               Section 9.

         (b)   "Board" shall mean the Board of Directors of the Company.

         (c)   "Code" shall mean the Internal Revenue Code of 1986, as amended
               from time to time.

         (d)   "Committee" shall mean the Compensation Committee of the Board or
               such other committee established by the Board to administer the
               Plan, provided that, if no such Committee is established by the
               Board, Committee shall mean the entire Board.

         (e)   "Common Stock" shall mean shares of common stock, no par value
               per share, of the Company.

         (f)   "Company" shall mean Ambulatory Resource Centres, Inc., a
               corporation organized under the laws of the State of Tennessee,
               or any successor corporation.

         (g)   "Disability" shall mean a Grantee's inability to perform his
               duties with the Company or any of its affiliates by reason of any
               medically


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               determinable physical or mental impairment, as determined by a
               physician selected by the Grantee and acceptable to the Company.

         (h)   "Exchange Act" shall mean the Securities Exchange Act of 1934, as
               amended from time to time, and as now or hereafter construed,
               interpreted and applied by regulations, rulings and cases.

         (i)   "Fair Market Value" per share as of a particular date shall mean
               (i) the closing sales price per share of Common Stock on the
               national securities exchange on which the Common Stock is
               principally traded for the last preceding date on which there was
               a sale of such Common Stock on such exchange, or (ii) if the
               shares of Common Stock are then traded in an over-the-counter
               market, the average of the closing bid and asked prices for the
               shares of Common Stock in such over-the-counter market for the
               last preceding date on which there was a sale of such Common
               Stock in such market, or (iii) if the shares of Common Stock are
               not then listed on a national securities exchange or traded in an
               over-the-counter market, such value as the Committee, in its sole
               discretion, shall determine.

         (j)   "Grantee" shall mean a person who receives a grant of Options
               under the Plan.

         (k)   "Incentive Stock Option" shall mean any option intended to be,
               and designated as, an incentive stock option within the meaning
               of Section 422 of the Code.

         (l)   "Insider" shall mean a Grantee who is subject to the reporting
               requirements of Section 16(a) of the Exchange Act.

         (m)   "Option" or "Options" shall mean a grant to a Grantee of an
               option or options to purchase shares of Common Stock. Options
               granted by the Committee pursuant to the Plan shall constitute
               either Incentive Stock Options or Non-qualified Stock Options.

         (n)   "Option Agreement" shall mean an agreement entered into between
               the Company and a Grantee in connection with a grant under the
               Plan.

         (o)   "Option Price" shall mean the exercise price of the shares of
               Common Stock covered by an Option.

         (p)   "Parent" shall mean any company (other than the Company) in an
               unbroken chain of companies ending with the Company if, at the
               time of granting an Option, each of the companies other than the
               Company owns stock possessing fifty percent (50%) or more of the
               total combined

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               voting power of all classes of stock in one of the other
               companies in such chain.



         (q)   "Plan" means this Ambulatory Resource Centres, Inc. 1997 Stock
               Option Plan, as amended from time to time.

         (r)   "Rule 16b-3" shall mean Rule 16b-3, as from time to time in
               effect, promulgated by the Securities and Exchange Commission
               under Section 16 of the Exchange Act, including any successor to
               such Rule.

         (s)   "Subsidiary" shall mean any company (other than the Company) in
               an unbroken chain of companies beginning with the Company if, at
               the time of granting an Option, each of the companies other than
               the last company in the unbroken chain owns stock possessing
               fifty percent (50%) or more of the total combined voting power of
               all classes of stock in one of the other companies in such chain.

         (t)   "Ten Percent Stockholder" shall mean a Grantee who, at the time
               an Incentive Stock Option is granted, owns stock possessing more
               than ten percent (10%) of the total combined voting power of all
               classes of stock of the Company or any Parent or Subsidiary.

3.       Administration.

         The Plan shall be administered by the Committee. The Committee shall
have the authority in its discretion, subject to and not inconsistent with the
express provisions of the Plan, to administer the Plan and to exercise all the
powers and authorities either specifically granted to it under the Plan or
necessary or advisable in the administration of the Plan, including, without
limitation, the authority to grant Options, to determine which Options shall
constitute Incentive Stock Options and which Options shall constitute
Nonqualified Stock Options; to determine the purchase price of the shares of
Common Stock covered by each Option; to determine the persons to whom, and the
time or times at which awards shall be granted; to determine the number of
shares to be covered by each award; to interpret the Plan; to prescribe, amend
and rescind rules and regulations relating to the Plan; to determine the terms
and provisions of the Option Agreements (which need not be identical); to
accelerate exercisability of awards; and to grant waivers of or cancel or
suspend awards, as necessary; and to make all other determinations deemed
necessary or advisable for the administration of the Plan.

         The Committee may delegate to one or more of its members or to one or
more agents such administrative duties as it may deem advisable, and the
Committee or any person to whom it has delegated duties as aforesaid may employ
one or more persons to render advice with respect to any responsibility the
Committee or such person may have under the Plan. All decisions, determinations
and interpretations

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<PAGE>

of the Committee shall be final and binding on all Grantees of any awards under
this Plan.

         The Board shall fill all vacancies, however caused, in the Committee.
The Board may from time to time appoint additional members to the Committee, and
may at any time remove one or more Committee members and substitute others. One
member of the Committee shall be selected by the Board as chairman. The
Committee shall hold its meetings at such times and places as it shall deem
advisable. All determinations of the Committee shall be made by a majority of
its members either present in person or participating by conference telephone at
a meeting or by written consent. The Committee may appoint a secretary and make
such rules and regulations for the conduct of its business as it shall deem
advisable, and shall keep minutes of its meetings.

         No member of the Board or Committee shall be liable for any action
taken or determination made in good faith with respect to the Plan or any award
granted hereunder.

4.       Eligibility.

         Awards may be granted to directors, executive officers and other key
employees and consultants of the Company or its Subsidiaries, including officers
and directors who are employees, except as proscribed by the Exchange Act or the
Code. In determining the persons to whom awards shall be granted and the number
of shares to be covered by each award, the Committee shall take into account the
duties of the respective persons, their present and potential contributions to
the success of the Company and such other factors as the Committee shall deem
relevant in connection with accomplishing the purpose of the Plan.

5.       Stock

         The maximum number of shares of Common Stock reserved for the grant of
awards under the Plan shall be 263,888 subject to adjustment as provided in
Section 9 hereof. Such shares may, in whole or in part, be authorized but
unissued shares or shares that shall have been or may be reacquired by the
Company. The maximum number of shares with respect to which awards may be
granted during any calendar year to any individual shall be 75,000.

         If any outstanding award under the Plan should, for any reason expire,
be canceled or be forfeited without having been exercised in full, the shares of
Common Stock allocable to the unexercised, canceled or terminated portion of
such award shall (unless the Plan shall have been terminated) become available
for subsequent grants of awards under the Plan.



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<PAGE>

6.       Terms and Conditions of Options.

         Each Option granted pursuant to the Plan shall be evidenced by an
Option Agreement, in the form of Exhibit A hereto or such other form and
containing such terms and conditions as the Committee shall from time to time
approve. Each Option shall be subject to the following terms and conditions,
except to the extent otherwise specifically provided in such Option Agreement:

         (a)   Number of Shares. Each Option Agreement shall state the number of
               shares of Common Stock to which the Option relates.

         (b)   Type of Option. Each Option Agreement shall specifically state
               that the Option constitutes an Incentive Stock Option or a
               Nonqualified Stock Option.

         (c)   Option Price. Each Option Agreement shall state the Option Price,
               which, in the case of an Incentive Stock Option, shall not be
               less than one hundred percent (100%) of the Fair Market Value of
               the shares of Common Stock covered by the Option on the date of
               grant. The Option Price shall be subject to adjustment as
               provided in Section 9 hereof. The date as of which the Committee
               adopts a resolution expressly granting an Option shall be
               considered the day on which such Option is granted.

         (d)   Medium and Time of Payment. The Option Price shall be paid in
               full, at the time of exercise, in cash or in shares of Common
               Stock having a Fair Market Value equal to such Option Price or in
               a combination of cash and Common Stock or in such other manner as
               the Committee shall determine, including a cashless exercise
               procedure through a broker-dealer.

         (e)   Term and Exercisability of Options. Each Option Agreement shall
               provide the exercise schedule for the Option as determined by the
               Committee, provided that the Committee shall have the authority
               to accelerate the exercisability of any outstanding Option at
               such time and under such circumstances as it, in its sole
               discretion, deems appropriate. The exercise period will be
               fifteen (15) years from the date of the grant of the Option
               unless otherwise determined by the Committee; provided that, in
               the case of an Incentive Stock Option, such exercise period shall
               not exceed ten (10) years from the date of grant of such Option.
               The exercise period shall be subject to earlier termination as
               provided in Section 6(f) hereof. An Option may be exercised, as
               to any or all full shares of Common Stock as to which the Option
               has become exercisable, by written notice delivered in person or
               by mail to the Secretary of the Company, specifying the number of


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<PAGE>

               shares of Common Stock with respect to which the Option is being
               exercised.

         (f)   Termination. Except as provided in this Section 6(f), an Option
               may not be exercised unless the Grantee is then in the employ of
               or is a director or is maintaining a consultant relationship with
               the Company or a Subsidiary thereof (or a company or a Parent or
               Subsidiary company of such company issuing or assuming the Option
               in a transaction to which Section 424(a) of the Code applies),
               and unless the Grantee has remained continuously so employed or
               in the director or consultant relationship since the date of
               grant of the Option. In the event that the employment or director
               or consultant relationship of a Grantee shall terminate, all
               Options of such Grantee that are exercisable at the time of such
               termination may, unless earlier terminated in accordance with
               their terms, be exercised within ninety (90) days after the date
               of such termination (or such longer period as the Committee shall
               prescribe) and all Options that are nonexercisable at the time of
               such termination shall terminate at such time.

         (g)   Other Provisions. The Option Agreements evidencing awards under
               the Plan shall contain such other terms and conditions not
               inconsistent with the Plan as the Committee may determine.

7.       Nonqualified Stock Options.

         Options granted pursuant to this Section 7 are intended to constitute
Nonqualified Stock Options and shall be subject only to the general terms and
conditions specified in Section 6 hereof.

8.       Incentive Stock Options

         Options granted pursuant to this Section 8 are intended to constitute
Incentive Stock Options and shall conform to the requirements of Section 422 of
the Code (or successor to such Section) and shall be subject to the following
special terms and conditions, in addition to the general terms and conditions
specified in Section 6 hereof.

         (a)   Value of Shares. The aggregate Fair Market Value (determined as
               of the date the incentive Stock Option is granted) of the shares
               of Common Stock with respect to which Incentive Stock Options
               granted under this Plan and all other option plans of any
               subsidiary become exercisable for the first time by any Grantee
               during any calendar year shall not exceed $100,000.

         (b)   Ten Percent Stockholder. In the case of an Incentive Stock Option
               granted to a Ten Percent Stockholder, (i) the Option Price shall
               not be

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<PAGE>

               less than one hundred ten percent (110%) of the Fair Market Value
               of the shares of Common Stock on the date of grant of such
               Incentive Stock Option, and (ii) the exercise period shall not
               exceed five (5) years from the date of grant of such Incentive
               Stock Option.

9.       Effect of Certain Changes.

         (a)   In the event of any extraordinary dividend, stock dividend,
               recapitalization, reclassification, merger, consolidation, stock
               split, warrant or rights issuance, or combination or exchange of
               such shares, or other similar transactions, the number of shares
               of Common Stock available for awards, the number of such shares
               covered by outstanding awards, and the price per share of Options
               shall be equitably adjusted by the Committee to reflect such
               event and preserve the value of such awards; provided, however,
               that any fractional shares resulting from such adjustment shall
               be eliminated.

         (b)   If, while any awards remain outstanding under the Plan, any of
               the following events shall occur (which events shall constitute a
               "Change in Control of the Company")-

               (i)   any "person," as such term is used in Sections 13(d) and
                     14(d) of the Exchange Act (other than (1) the Company, (2)
                     any trustee or other fiduciary holding securities under an
                     employee benefit plan of the Company or any of its
                     Subsidiaries, or (3) any corporation owned, directly or
                     indirectly, by the stockholders of the Company in
                     substantially the same proportions as their ownership of
                     Common Stock), is or becomes the "beneficial owner" (as
                     defined in Rule 13d-3 under the Exchange Act), directly or
                     indirectly, of securities of the Company representing more
                     than 50% of the combined voting power of the Company's then
                     outstanding voting securities;

               (ii)  during any period of not more than two consecutive years,
                     not including any period prior to the adoption of this
                     Plan, individuals who at the beginning of such period
                     constitute the Board, and any new director (other than a
                     director designated by a person who has entered into an
                     agreement with the Company to effect a transaction
                     described in clause (i), (iii), or (iv) of this Section
                     9(b)) whose election by the Board or nomination for
                     election by the Company's stockholders was approved by a
                     vote of at least two-thirds (2/3) of the directors then
                     still in office who either were directors at the beginning
                     of the period or whose election or nomination for election
                     was

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<PAGE>

                     previously so approved, cease for any reason to constitute
                     at least a majority thereof;

               (iii) the stockholders of the Company approve a merger or
                     consolidation of the Company with any other corporation,
                     other than (A) a merger or consolidation which would result
                     in the voting securities of the Company outstanding
                     immediately prior thereto continuing to represent (either
                     by remaining outstanding or by being converted into voting
                     securities of the surviving or parent entity) 50% or more
                     of the combined voting power of the voting securities of
                     the Company or such surviving or parent entity outstanding
                     immediately after such merger or consolidation or (B) a
                     merger or consolidation in which no "person" (as
                     hereinabove defined) acquired 50% or more of the combined
                     voting power of the Company's then outstanding securities;
                     or

               (iv)  the stockholders of the Company approve a plan of complete
                     liquidation of the Company or an agreement for the sale or
                     disposition by the Company of all or substantially all of
                     the Company's assets (or any transaction having a similar
                     effect) -

         then from and after the date on which any such Change in Control shall
         have occurred (the "Acceleration Date"), the award covered by such
         Agreement shall be exercisable or otherwise nonforfeitable in full,
         whether or not otherwise exercisable or forfeitable.

         (c)   In the event of a change in the Common Stock of the Company as
               presently constituted that is limited to a change of all of its
               authorized shares of Common Stock into the same number of shares
               with a different par value or without par value, the shares
               resulting from any such change shall be deemed to be the Common
               Stock within the meaning of the Plan.

10.      Period During Which Awards May Be Granted.

         Awards may be granted pursuant to the Plan from time to time within a
period of ten (10) years from the date the Plan is adopted by the Board.

11.      Transferability of Awards.

         No award shall be transferable or assignable, or exercisable by, anyone
other than the Grantee to whom it was granted, except (i) by law, will or the
laws of descent and distribution, (ii) as a result of the disability of a
Grantee or (iii) that the Committee (in the form of the Option Agreement or
otherwise) may permit transfers of awards by gift or otherwise to a member of a
Grantee's immediate


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family and/or trusts whose beneficiaries are members of the Grantee's immediate
family, or to such other persons or entities as may be approved by the
Committee. Notwithstanding the foregoing, in no event shall Incentive Stock
Options be transferable or assignable other than by will or by the laws of
descent and distribution.

12.      Approval of Stockholders.

         The Plan shall take effect upon its adoption by the Board but the Plan
(and any grants of awards made prior to the stockholder approval mentioned
herein) shall be subject to the approval of the holder(s) of a majority of the
issued and outstanding shares of voting securities of the Company entitled to
vote, which approval must occur within twelve months of the date the Plan is
adopted by the Board.

13.      Agreement by Grantee Regarding Withholding Taxes.

         If the Committee shall so require, as a condition of exercise of an
Option, (a "Tax Event"), each Grantee shall agree that no later than the date of
the Tax Event, the Grantee will pay to the Company or make arrangements
satisfactory to the Committee regarding payment of any federal, state or local
taxes of any kind required by law to be withheld upon the Tax Event.
Alternatively, the Committee may provide that a Grantee may elect, to the extent
permitted or required by law, to have the Company deduct federal, state and
local taxes of any kind required by law to be withheld upon the Tax Event from
any payment of any kind due to the Grantee. The withholding obligation may be
satisfied by the withholding or delivery of Common Stock.

14.      Amendment and Termination of the Plan.

         The Board may amend, modify, suspend or terminate the Plan for the
purpose of meeting or addressing any changes in legal requirements or for any
other purpose permitted by law. Subject to changes in law or other legal
requirements that would permit otherwise, the Plan may not be amended without
the consent of the holders of a majority of the shares of Common Stock then
outstanding to increase the aggregate number of shares of Common Stock that may
be issued under the Plan (except for adjustments pursuant to Section 9(a).
Except as provided in Section 9(a) hereof, no suspension, termination,
modification or amendment of the Plan may adversely affect any award previously
granted without the written consent of the Grantee.

15.      Rights as a Shareholder.

         A Grantee or a transferee of an award shall have no rights as a
shareholder with respect to any shares covered by the award until the date of
the issuance of a stock certificate to him for such shares. No adjustment shall
be made for dividends

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(ordinary or extraordinary, whether in cash, securities or other property) or
distribution of other rights for which the record date is prior to the date such
stock certificate is issued, except as provided in Section 9(a) hereof.

16.      No Rights to Employment.

         Nothing in the Plan or in any award granted or Agreement entered into
pursuant hereto shall confer upon any Grantee the right to continue in the
employ of, or in a consultant relationship with, the Company or any Subsidiary
or to be entitled to any remuneration or benefits not set forth in the Plan or
such Agreement or to interfere with or limit in any way the right of the Company
or any such Subsidiary to terminate such Grantee's employment. Awards granted
under the Plan shall not be affected by any change in duties or position of a
Grantee as long as such Grantee continues to be employed by, or in a consultant
relationship with, the Company or any Subsidiary.

17.      Beneficiary.

         A Grantee may file with the Committee a written designation of a
beneficiary on such form as may be prescribed by the Committee and may, from
time to time, amend or revoke such designation. If no designated beneficiary
survives the Grantee, the executor or administrator of the Grantee's estate
shall be deemed to be the Grantee's beneficiary.

18.      Governing Law.

         The Plan and all determinations made and actions taken pursuant hereto
shall be governed by the laws of the State of Tennessee, without regard to its
conflicts of laws principles.

19.      Effective Date and Duration of the Plan.

         This Plan shall be effective as of the date it is approved or ratified
by the stockholders of the Company, and shall terminate on the later of (a) the
tenth anniversary of such date or (b) the last expiration of awards granted
hereunder.

[Adopted by Actions of the Board and the Shareholders of the Company taken by
written consent on May 27, 1997, and amended by Actions of the Board and the
Shareholders of the Company taken by written consent on September 22, 1998.]


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<PAGE>


                             STOCK OPTION AGREEMENT

         AGREEMENT dated as of ______, 199_, by and between Ambulatory Resource
Centres, Inc., a Tennessee corporation (the "Company"), and ____________________
(the "Grantee").

         WHEREAS, the Company has adopted the Ambulatory Resource Centres, Inc.
1997 Stock Option Plan (the "Plan") and the Company's stockholders have approved
such adoption; and

         WHEREAS, the Company desires to grant to the Grantee an option under
the Plan to acquire an aggregate of shares of the Company's common stock, no par
value (the "Common Stock"), on the terms set forth herein.

         NOW, THEREFORE, the parties agree as follows:

         1. Definitions. Capitalized terms not otherwise defined herein shall
have the meanings set forth in the Plan.

         2. Grant of Option. The Grantee is hereby granted a Nonqualified Stock
Option (the "Option") to purchase an aggregate of _____ shares of Common Stock
pursuant to the terms of this Agreement and the provisions of the Plan.

         3. Option Price. The exercise price of the Option shall be $_____ per
share of Common Stock issuable thereunder.

         4. Conditions to Exercisability.

                  (a) The Option will vest and become exercisable on each of the
first three anniversaries of the date hereof with respect to thirty-three and
one-third percent (33 1/3 %) of the shares of Common Stock covered thereby if
the Grantee continues to be employed by the Company on each such date.

                  (b) Notwithstanding the foregoing, the Option shall become
exercisable in full upon the occurrence of either (i) a Change in Control of the
Company or (ii) a Qualifying IPO.

                  (c) Notwithstanding the foregoing, the Option shall become
exercisable, in whole or in part, at any time at the discretion of the
Compensation Committee of the Company's Board of Directors or the entire Board
of Directors if no such Committee has been appointed (the "Committee").

         5. Period of Option. The Option shall expire on the earliest to occur
of:

                  (a) the tenth anniversary of the date hereof:


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<PAGE>

                  (b) the first anniversary of the Grantee's death or
termination of employment for Disability; and

                  (c) three months after the Grantee's termination of employment
other than for death or

         Notwithstanding the foregoing, upon any termination from employment the
Option shall immediately terminate in respect of any portion thereof
nonexercisable at the time of such termination.

         6. Exercise of Option.

                  (a) The Option shall be exercised in the following manner: the
Grantee, or the person or persons having the right to exercise the Option upon
the death or Disability of the Grantee, shall deliver to the Company written
notice specifying the number of shares of Common Stock which the Grantee elects
to purchase. The Grantee (or such other person) must either (i) include with
such notice full payment of the exercise price for the Common Stock being
purchased pursuant to such notice or (ii) provide for a broker-dealer to forward
such full payment to the Company, in a manner and in a period of time acceptable
to the Company, in a cashless exercise procedure. Payment of the exercise price
must be made (i) in cash, (ii) by certified or cashier's check, (iii) by
delivery to the Company of Common Stock previously owned for at least six months
and having a Fair Market Value equal to the aggregate exercise price, or (iv) in
a combination of cash, check and Common Stock. In lieu of the payment of the
exercise price as set forth in the foregoing sentence, upon request of the
Grantee (or such other person), the Company may, in its sole discretion, allow
the Grantee to exercise the Option or a portion thereof by tendering shares of
Common Stock previously owned for less than six months, including shares
received upon exercise of such Option.

                  (b) Upon the request of the Grantee, or the person or persons
having the right to exercise the Option upon the death or Disability of the
Grantee, the Company may, in its sole discretion, in lieu of a normal issuance
of shares upon exercise of the Option in whole or in part, pay the Grantee in
cash, Common Stock or a combination of cash and Common Stock, as the Company
shall determine, in an amount determined by multiplying (i) the excess of the
Fair Market Value of a share of Common Stock on the date of exercise of such
Option over the per share exercise price of the Option by (ii) the number of
shares of Common Stock as to which the Option is being exercised.

                  (c) Full payment of the exercise price for shares subject to
the Option and any applicable federal and state withholding tax shall be made at
the time of exercise of any portion of the Option. No shares shall be issued
until full payment has been made, and the Grantee shall have none of the rights
of a stockholder until shares are issued to him. The Company may authorize, but
shall

                                       2
<PAGE>

have no obligation to permit, the payment of any applicable federal or state
withholding tax by the tender of shares of Common Stock, including the tender of
shares which otherwise would be issued to the Grantee upon exercise of the
Option, provided, however, that any such payment by a director or officer
subject to Section 16(b) of the Exchange Act shall be in compliance with Rule
16b-3.

                  (d) If the Plan or any law, regulation or interpretation
requires the Company to take any action regarding the Common Stock before the
Company issues certificates for the Common Stock being purchased, the Company
may delay delivering the certificates for the Common Stock for the period
necessary to take such action. The certificate or certificates representing the
Common Stock acquired pursuant to the Option may bear a legend restricting the
transfer of such Common Stock, and the Company may impose stop transfer
instructions to implement such restrictions, if applicable.

                  (e) The Grantee will not be deemed to be a holder of any
shares pursuant to exercise of the Option until the date of the issuance of a
stock certificate to him for such shares of Common Stock and until the shares of
Common Stock are paid for in full.

                  (f) Notwithstanding the foregoing, in the event Grantee
exercises any of the Option prior to the time the Company consummates a firm
commitment underwritten public offering of its common stock pursuant to the
Securities Act of 1933, as amended (a "Qualifying IPO") which provides proceeds
to the Company of at least $20 million after the deduction of underwriting
discounts and commissions but before the deduction of other expenses of
issuance, then as a condition to each and every exercise of the Option the
Grantee shall execute (if no such Agreement has heretofore been executed by the
Grantee) an Agreement (in such form requested by the Company) granting first the
Company and then the other stockholders of the Company a 30 day right of first
refusal in respect of any future sale of such shares by the Grantee, such
restriction described above to terminate upon the Qualifying IPO.

         7. Representations.

                  (a) The Company represents and warrants that this Agreement
has been authorized by all necessary corporate action of the Company and is a
valid and binding agreement of the Company enforceable against the Company in
accordance with its terms.

                  (b) The Grantee represents and warrants that he is not a party
to any agreement or instrument which would prevent him from entering into or
performing his duties in any way under this Agreement.

         8. Entire Agreement. This Agreement contains all the understandings
between the parties hereto pertaining to the matters referred to herein, and


                                       3
<PAGE>

supersedes all undertakings and agreements, whether oral or in writing,
previously entered into by them with respect thereto. The Grantee represents
that, in executing this Agreement, he does not rely and has not relied upon any
representation or statement not set forth herein made by the Company with regard
to the subject matter, bases or effect of this Agreement or otherwise.

         9. Amendment or Modification Waiver. No provision of this Agreement may
be amended or waived unless such amendment or waiver is agreed to in writing,
signed by the Grantee and by a duly authorized officer of the Company. No waiver
by any party hereto or any breach by another party hereto of any condition or
provision of this Agreement to be performed by such other party shall be deemed
a waiver of a similar or dissimilar condition or provision at the same time, any
prior time or any subsequent time.

         10. Notices. Any notice to be given hereunder shall be in writing and
shall be deemed given when delivered personally, sent by courier or telecopy or
registered or certified mail, postage prepaid, return receipt requested,
addressed to the party concerned at the address indicated below or to such other
address as such party may subsequently give notice of hereunder in writing:

                  To Grantee at:

                  The Grantee's residence address
                  then on file with the Company's or its affiliates'
                  Human Resources Department

                  To the Company at:

                  -----------------------------------------------


                  -----------------------------------------------
                  Attn: President

         Any notice delivered personally or by courier under this Section 10
shall be deemed given on the date delivered and any notice sent by telecopy or
registered or certified mail, postage prepaid, return receipt requested, shall
be deemed given on the date telecopied or mailed.

         11. Severability. If any provision of this Agreement or the application
of any such provision to any party or circumstances shall be determined by any
court of competent jurisdiction to be invalid and unenforceable to any extent,
the remainder of this Agreement or the application of such provision to such
person or circumstances other than those to which it is so determined to be
invalid and unenforceable, shall not be affected thereby, and each provision
hereof shall be validated and shall be enforced to the fullest extent permitted
by law.

         12. Transferability. This Option (or any portion thereof) is not
transferable by the Grantee except (i) by law, by will or by the laws of descent
and distribution or

                                       4
<PAGE>

(ii) that the Committee may permit transfers of this Option (or any portion
thereof) by gift or otherwise to a member of a Grantee's immediate family and/or
trusts whose beneficiaries are members of the Grantee's immediate family, or to
such other persons or entities as may be approved by the Committee.

         13. Survivorship. The respective rights and obligations of the parties
hereunder shall survive any termination of this Agreement to the extent
necessary to the intended preservation of such rights and obligations.

         14. Governing Law. This agreement will be governed by and construed in
accordance with the laws of the State of Tennessee, without regard to its
conflicts of laws principles.

         15. Headings. All descriptive headings of sections and paragraphs in
this Agreement are intended solely for convenience, and no provision of this
Agreement is to be construed by reference to the heading of any section or
paragraph.

         16. Construction. This Agreement is made under and subject to the
provisions of the Plan, and all of the provisions of the Plan are hereby
incorporated herein as provisions of this Agreement. If there is a conflict
between the provisions of this Agreement and the provisions of the Plan, the
provisions of the Plan will govern. By signing this Agreement, the Grantee
confirms that he has received a copy of the Plan and has had an opportunity to
review the contents thereof.

         17. Counterparts. This Agreement may be executed in counterparts, each
of which shall be deemed an original, but all of which together shall constitute
one and the same instrument.

         18. Company Call Option on Option Shares. If Grantee's employment with
the Company shall cease or terminate for any reason, or no reason, with or
without cause, including, without limitation, involuntary termination, death or
temporary or permanent disability, prior to the earlier of (i) the third
anniversary of the date hereof and (ii) a Qualifying IPO (a "Call Event"), then
the Company shall have an irrevocable option to purchase, and Grantee shall be
required to sell, any or all of the shares of common stock of the Company
purchased pursuant to this Agreement (the "Option Shares") at a purchase price
of $____ per share plus 8% interest from the date each Option Share was
purchased by the Grantee until purchased by the Company pursuant to this Option;
provided, however, that the Company may not without the consent of Grantee
purchase less than all Option Shares then owned by Grantee. If the Company
desires to exercise its option to purchase any Option Shares pursuant to this
Section 18, the Company shall, no later than 6 months following the date of the
Call Event; give written notice of its intention to purchase the Option Shares
to Grantee specifying the number of Option Shares it desires to purchase.
Notwithstanding the foregoing, the provisions of this Section 18 shall



                                       5
<PAGE>

terminate upon either (i) the occurrence of a Change of Control of the Company
or (ii) the occurrence of a Qualifying IPO.

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

                                  AMBULATORY RESOURCE CENTRES, INC.


                                  By:
                                      ----------------------------------------


                                  Grantee:


                                  --------------------------------------------


                                       6