LIMITED LIABILITY COMPANY AGREEMENT
                        OF PRIME/BDEC ACQUISITION, L.L.C.
     Organized under the Delaware Limited Liability Company Act (the "Act").

                                   ARTICLE I.
                                NAME AND LOCATION

     Section 1.1. Name. The name of this limited liability company is Prime/BDEC
Acquisition, L.L.C. (the "Company"). ----

         Section  1.2.  Members.  The  only  members  of the  Company  upon  the
execution of this Limited Liability Company Agreement (this  "Agreement")  shall
be Prime Medical Operating,  Inc, a Delaware corporation  ("Prime"),  and Barnet
Dulaney Eye Center,  P.L.L.C., an Arizona professional limited liability company
("BDEC"). For purposes of this Agreement, the "Members" shall include such named
members and any new members  admitted  pursuant to the terms of this  Agreement,
but does not  include  any person or entity who has ceased to be a member in the
Company.

     Section 1.3. Principal Office. The principal office of the Company shall be
located in 1301 Capital of Texas Hwy., Suite C-300, Austin, Texas 78746-6550, or
such other location as may be selected by the Members. ----------------

     Section 1.4. Registered Agent and Address. The name of the registered agent
and the  address  of the  registered  office of the  Company as set forth in the
Certificate of Formation of the Company are: -----------------------------
                                            The Corporation Trust Company
                                            1209 Orange Street
                                            Wilmington, Delaware 19801

     Section 1.5.  Other  Offices.  Other offices and other  facilities  for the
transaction of business shall be located at such places as the Managers may from
time to time determine. -------------

         Section 1.6  Contribution  Agreement.  The Company was initially formed
with a single member,  BDEC, for the purpose of  consummating  the  transactions
contemplated by that certain Contribution Agreement dated effective September 1,
1999, by and among Prime, Prime Medical Services,  Inc., a Delaware  corporation
("PMSI"), BDEC, the Company,  Prime/BDR Acquisition,  L.L.C., a Delaware limited
liability  company,  LASIK  Investors,  L.L.C.,  a  Delaware  limited  liability
company, David D. Dulaney, M.D., Ronald W. Barnet, M.D., and Mark Rosenberg (the
"Contribution  Agreement").  The  parties  have  executed  this  Agreement  upon
consummation of the  transactions  contemplated by the  Contribution  Agreement.
This agreement  supercedes and replaces any prior membership  agreement or other
governing or organizational document of the Company.

                                                    ARTICLE II.
                                                    MEMBERSHIP

     Section 2.1. Members' Interests.  The "Membership  Interest" of each Member
is set forth on Exhibit A. ------------------ ---------

     Section 2.2. Admission to Membership. The admission of new Members shall be
only by the vote of the Managers  pursuant to Section 8.9 hereof. If new Members
are admitted,  this Agreement shall be amended to reflect each Member's  revised
Membership Interest. -----------------------

     Section 2.3.  Property  Rights.  No Member shall have any right,  title, or
interest in any of the property or assets of the Company. ---------------

     Section  2.4.  Liability  of  Members.  No Member of the  Company  shall be
personally  liable for any debts,  liabilities,  or  obligations of the Company,
including under a judgment decree, or order of court. --------------------

         Section 2.5.  Transferability of Membership.  Except as provided below,
Membership  Interests in the Company are  transferable  only with the  unanimous
written  consent  of all  Members.  If such  unanimous  written  consent  is not
obtained when  required,  the  transferee  shall be entitled to receive only the
share of  profits  or other  compensation  by way of  income  and the  return of
contributions  to which  the  transferor  Member  otherwise  would be  entitled.
Notwithstanding  the  foregoing,  (i) the  Membership  Interests of Prime may be
freely  transferred,  without  consent,  to any  entity  that is then  owned  or
controlled,  directly or indirectly, by Prime Medical Services, Inc., a Delaware
corporation (or its successor in interest), (ii) the Membership Interests of any
Member  may be  freely  assigned,  pledged  or  otherwise  transferred,  without
consent,  to  secure  any debt,  liability  or  obligation  owed to Prime by the
Company,  any  Member  or any  entity  affiliated  with the  Company,  (iii) the
Membership Interests of any Member may be freely assigned,  pledged or otherwise
transferred,  without  consent,  in  favor  of the  Lender(s)  under,  or by the
Lender(s)  as a result  of the  enforcement  of any  security  interest  arising
pursuant to, that certain  Senior  Credit  Facility  (the "Credit  Facility") of
PMSI, and (iv) the pledge by BDEC  (pursuant to Section 6.3 of the  Contribution
Agreement) of its right to receive  distributions from the Company in respect of
its  Membership  Interest  shall not be deemed to violate any  provision of this
Agreement.

     Section 2.6.  Resignation  of Members.  A Member may not withdraw  from the
Company except on the unanimous consent of the remaining  Members.  The terms of
the Members  withdrawal  shall be determined by agreement  between the remaining
Members and the withdrawing Member. ----------------------

                                                   ARTICLE III.
                                                 MEMBERS' MEETINGS

     Section 3.1.  Time and Place of Meeting.  All meetings of the Members shall
be held at such time and at such place  within or without  the State of Delaware
as shall be determined by the Managers. -------------------------

     Section 3.2. Annual Meetings.  In the absence of an earlier meeting at such
time and place as the Managers  shall  specify,  annual  meetings of the Members
shall be held at the principal office of the Company on the date which is thirty
(30) days after the end of the Company's fiscal year if not a legal holiday, and
if a legal holiday, then on the next full business day following, at 10:00 a.m.,
at which  meeting the  Members may  transact  such  business as may  properly be
brought before --------------- the meeting.

     Section  3.3.  Special  Meetings.  Special  meetings  of the Members may be
called at any time by any Member.  Business transacted at special meetings shall
be   confined   to  the   purposes   stated  in  the  notice  of  the   meeting.
----------------

         Section 3.4.  Notice.  Written or printed notice stating the place, day
and hour of any Members'  meeting,  and, in the case of a special  meeting,  the
purpose or purposes for which the meeting is called, shall be delivered not less
than ten (10) days nor more than thirty (30) days before the date of the special
meeting,  either  personally  or by mail,  by or at the  direction of the person
calling the meeting, to each Member entitled to vote at such meeting. If mailed,
such notice shall be deemed to be delivered three (3) days after it is deposited
in the United States mail,  postage prepaid,  to the Member at his address as it
appears on the records of the Company at the time of mailing.

         Section 3.5. Quorum. Members present in person or represented by proxy,
holding  more than fifty  percent  (50%) of the total votes which may be cast at
any meeting  shall  constitute  a quorum at all  meetings of the Members for the
transaction  of  business.  If,  however,  such  quorum  shall not be present or
represented at any meeting of the Members, the Members entitled to vote, present
in person or represented by proxy,  shall have power to adjourn the meeting from
time to time,  without notice other than  announcement  at the meeting,  until a
quorum shall be present or represented. When any adjourned meeting is reconvened
and a quorum shall be present or  represented,  any  business may be  transacted
which might have been  transacted at the meeting as originally  noticed.  Once a
quorum is constituted,  the Members present or represented by proxy at a meeting
may  continue  to  transact  business  until  adjournment,  notwithstanding  the
subsequent  withdrawal therefrom of such number of Members as to leave less than
a quorum.

         Section  3.6.  Voting.  Members  shall  only  be  required  to  vote in
instances  or with  respect  to  matters  where  member  voting is  required  by
applicable  law or to the extent  expressly  contemplated  in Section 8.1.  With
respect to any act or  transaction  that  requires a vote by the  Members  under
applicable law, the affirmative  vote of not less than three (3) of the Managers
shall also be  required  in order to  approve  the act or  transaction,  in each
instance. Subject to the foregoing, when a quorum is present at any meeting, the
vote of the Members,  whether  present or  represented by proxy at such meeting,
holding  more than fifty  percent  (50%) of the total votes which may be cast at
any  meeting  shall be the act of the  Members,  unless the vote of a  different
number is required by the Act,  the  Certificate  of  Formation  or this Limited
Liability Company Agreement.  Each Member shall be entitled to one vote for each
percentage point represented by their Membership Interest. Fractional percentage
point  interests  shall be  entitled to a  corresponding  fractional  vote.  The
provisions of this Section shall not  interfere  with the  provisions of Section
8.9 relating to acts or transactions requiring the written approval of three (3)
or more Managers.  Each Member acknowledges and agrees that, in the event of any
exercise of the Repurchase  Option,  as defined in the  Contribution  Agreement,
each Member will vote its entire  Membership  Interest in favor of  transferring
the Company's assets pursuant to the Repurchase Option.

     Section 3.7.  Proxy.  Every proxy must be executed in writing by the Member
or by his  duly  authorized  attorney-in-fact,  and  shall  be  filed  with  the
Secretary of the Company prior to or at the time of the meeting.  No proxy shall
be  valid  after  eleven  (11)  months  from the  date of its  execution  unless
otherwise  provided  therein.  Each proxy shall be  revocable  unless  expressly
provided therein to be irrevocable and unless otherwise made irrevocable by law.
-----

     Section 3.8. Action by Written Consent. Any action required or permitted to
be taken at any  meeting  of the  Members  may be taken  without a meeting  if a
consent in writing, setting forth the action so taken, shall be signed by all of
the Members  entitled to vote with respect to the subject  matter  thereof,  and
such  consent  shall  have the same  force  and  effect as a  unanimous  vote of
Members. -------------------------

     Section 3.9. Meetings by Conference  Telephone.  Members may participate in
and hold  meetings  of  Members  by means of  conference  telephone  or  similar
communications  equipment  by means of which all  persons  participating  in the
meeting  can  hear  each  other,  and  participation  in  such a  meeting  shall
constitute   presence  in  person  at  such  meeting,   except  where  a  person
participates  in the  meeting  for  the  express  purpose  of  objecting  to the
transaction     of    any     business     on    the     ground     that     the
-------------------------------- meeting is not lawfully called or convened.

                                   ARTICLE IV.
                        MEMBERSHIP CAPITAL CONTRIBUTIONS

         Except  for  each  Member's  initial  capital   contribution   made  in
connection with the formation of the Company, no capital  contributions shall be
required  of any  Member  without  the  approval  of all the  Members  to  raise
additional capital, and only then proportionately as to each Member.

                                                    ARTICLE V.
                                              DISTRIBUTION TO MEMBERS

         At the end of each calendar quarter, subject only to the qualifications
and  limitations  set forth below,  the Company shall  distribute  its available
excess  earnings to its members,  to be divided  among them in  accordance  with
their Membership Interests.  Distributions in kind shall be made on the basis of
agreed value as determined by the Members.  Notwithstanding  the foregoing,  the
Company  may  not  make a  distribution  to its  Members  to  the  extent  that,
immediately  after giving effect to the  distribution,  all  liabilities  of the
Company,  other than  liabilities to the Members with respect to their interests
and  liabilities  for which the  recourse of  creditors  is limited to specified
property of the  Company,  exceed the fair value of the Company  assets;  except
that the fair value of property that is subject to liability for which  recourse
of  creditors  is limited,  shall be included in the Company  assets only to the
extent that the fair value of the property exceeds that liability.

                                   ARTICLE VI.
              ALLOCATION OF NET PROFITS AND LOSSES FOR TAX PURPOSES

         For  accounting  and income tax  purposes,  all items of income,  gain,
loss,  deduction,  and  credit of the  Company  for any  taxable  year  shall be
allocated  among the  Members in  accordance  with their  respective  Membership
Interests,  except as may be otherwise  required by the Internal Revenue Code of
1986, as amended.

                                  ARTICLE VII.
                           DISSOLUTION AND WINDING UP

     Section 7.1.  Dissolution.  Notwithstanding  any  provision of the Act, the
Company  shall be  dissolved  only  upon the  first of the  following  to occur:
-----------

          (a) Forty  (40)  years  from the date of  filing  the  Certificate  of
     Formation of the Company;

          (b) Written consent of all the then current Members to dissolution;

          (c) The bankruptcy of a Member, unless there is at least one remaining
     Member and such Member or, if more than one remaining Member, all remaining
     Members  agree to  continue  the  Company and its  business.  Section  7.2.
     Winding Up. Unless the Company is continued  pursuant to Section  7.1(c) of
     this Article VII., in the event of dissolution of the Company, the Managers
     (excluding  any  Manager(s)  holding  office  pursuant to  designation by a
     Member  subject to  bankruptcy  proceedings)  shall  wind up the  Company's
     affairs  as  soon  as  reasonably  practicable.  On the  winding  up of the
     Company,  the Managers shall pay and/or  transfer the assets of the Company
     in the following order: ----------

          (a) In discharging  liabilities (including loans from Members) and the
     expenses of concluding the Company's affairs; and

                  (b) The balance,  if any, shall be divided between the Members
in accordance with the Members' Membership Interests.

                                  ARTICLE VIII.
                                    MANAGERS

         Section 8.1. Selection of Managers.  Management of the Company shall be
vested in the  Managers.  Initially,  the Company  shall have four (4) Managers,
being Ken  Shifrin,  Joe Jenkins,  M.D.,  (as the initial  Manager  designees of
Prime),  David D.  Dulaney,  M.D.  and Ronald W. Barnet,  M.D.,  (as the initial
Manager  designees  of  BDEC).  Thereafter,  for so long as  there  are four (4)
Managers,  (a) Prime shall be entitled to designate two (2) of the Managers; and
(b) BDEC shall be entitled to designate  the  remaining two (2) of the Managers.
Notwithstanding  the foregoing,  a Member shall not be entitled to designate any
Manager unless its Membership Interest: (x) has not (other than as allowed under
Section 2.5 of this Agreement) been transferred, repurchased, assigned, pledged,
hypothecated  or in any way  alienated;  and (y) equals or exceeds forty percent
(40%) of the aggregate Membership Interests.  The Members may, by unanimous vote
of all Members,  from time to time, change the number of Managers of the Company
and remove or add Managers accordingly. A Manager shall serve as a Manager until
their  resignation  or removal  pursuant to Section  8.2 or 8.3 of this  Article
VIII.  Managers need not be residents of the State of Delaware or Members of the
Company.

          Section 8.2. Resignations. Each Manager shall have the right to resign
     at any time upon written notice of such resignation to the Members.  Unless
     otherwise  specified in such written  notice,  the  resignation  shall take
     effect upon the receipt thereof,  and acceptance of such resignation  shall
     not be  necessary  to make same  effective.  The  Member who  designated  a
     resigning  manager shall be entitled to designate the successor thereto and
     all Members agree to take such action as may be  ------------  necessary to
     cause the election of all such successor Managers.

          Section 8.3. Removal of Managers.  Any Manager may be removed,  for or
     without  cause,  at any time,  but only by the Member who  designated  such
     Manager,  upon the written notice to all Members. The Member who designated
     such removed  Manager shall be entitled to designate the successor  thereto
     and all Members  agree to take such action as may be necessary to cause the
     election of all such successor Managers. -------------------

         Section  8.4.  General  Powers.  The  business of the Company  shall be
managed by its Managers, which may, by the vote or written consent in accordance
with this  Agreement,  exercise any and all powers of the Company and do any and
all such  lawful  acts and  things  as are not by the Act,  the  Certificate  of
Formation or this Limited Liability Company Agreement directed or required to be
exercised or done by the Members, including, but not limited to, contracting for
or incurring on behalf of the Company debts,  liabilities and other obligations,
without the consent of any other person, except as otherwise provided herein.

          Section 8.5.  Place of Meetings.  The Managers of the Company may hold
     their  meetings,  both  regular and special,  either  within or without the
     State of Delaware. -----------------

          Section 8.6. Annual Meetings. The annual meeting of the Managers shall
     be held without further notice immediately  following the annual meeting of
     the  Members,  and at the same place,  unless by  unanimous  consent of the
     Managers that such time or place shall be changed. ---------------

          Section 8.7. Regular Meetings. Regular meetings of the Managers may be
     held  without  notice at such time and place as shall  from time to time be
     determined by the Managers. ----------------

          Section 8.8. Special Meetings.  Special meetings of the Mangers may be
     called by any Manager on seven (7) days notice to each  Manager,  with such
     notice  to be  given  personally,  by mail  or by  telecopy,  telegraph  or
     mailgram. ----------------

         Section  8.9.  Quorum and Voting.  At all  meetings of the Managers the
presence of at least three (3) Managers  shall be necessary  and  sufficient  to
constitute a quorum for the transaction of business, and the affirmative vote of
at least a majority of the  Managers  present at any meeting at which there is a
quorum shall be the act of the Managers, except as may be otherwise specifically
provided by the Act, the Contribution Agreement, the Certificate of Formation or
this Agreement. If a quorum shall not be present at any meeting of Managers, the
Managers  present there may adjourn the meeting from time to time without notice
other  than  announcement  at the  meeting,  until a quorum  shall  be  present.
Notwithstanding  any  other  Member  or  Manager  voting  or  quorum  provisions
contained  in  this  Agreement,  the  following  acts  or  transactions  by,  or
involving,  the Company shall  require the prior  written  approval of three (3)
Managers  (unless and to the extent a particular act or transaction is expressly
required of the Company pursuant to the terms and provisions of the Contribution
Agreement or any Transaction Document):

          (a) Any  amendment to the Company's  Certificate  of Formation or this
     Agreement.

          (b)  Mergers,  consolidations  or  combinations  of the  Company  with
     another limited liability company or other entity.

                  (c)  Purchase by the Company of any  interest in the  Company,
irrespective of the source of such interest.

          (d) Disposition,  sale, assignment or other transfer by the Company of
     any  interest  it owns in the  Company,  except that such  interest  may be
     extinguished without the approval required under this Article.

                  (e)      Issuance of any interest in the Company to any party.

                  (f) Dissolving,  liquidating,  or filing bankruptcy or seeking
relief under any debtor relief law.

                  (g)  Election  or removal of  officers,  and  establishing  or
changing the compensation for Managers, officers or other employees.

          (h) Not making any cash distributions to its Members that are required
     by this Agreement to be made, or making any distributions to its Members of
     cash or property that are prohibited under this Agreement.

          (i) Sale, lease or other transfer of all or  substantially  all of the
     Company's  assets,  or any assets other than in the ordinary  course of the
     Company's business.

                  (j)  Initiating  or  settling  any  litigation  or  regulatory
proceeding, or confessing any judgment.

                  (k) Hiring or  changing  the  Company's  accountants  or legal
counsel.

                  (l) Opening or closing bank or other depository accounts,  and
establishing or changing the signature  withdrawal authority with respect to any
such accounts.

          (m) Borrowing or incurring any indebtedness,  other than open accounts
     payable to  unaffiliated  third  parties,  or granting  any  collateral  or
     security  (by  way of  guaranty  or  otherwise)  for  any  indebtedness  or
     obligation.

                  (n)  Engaging in any act or  transaction  not in the  ordinary
course of the Company's business.

          (o)  Purchasing  or leasing  assets or property,  or entering into any
     contract or  obligation,  which  obligates  the Company to pay in excess of
     $10,000 in the aggregate in one or any series of installments.

          (p) Doing any  business  other than the  conduct of the  Business  (as
     defined in the Contribution Agreement) or causing a change in the nature of
     the business or the legal name of the Company.

                  (q)  Entering  into a  transaction  or other  action  with any
Manager, officer or Member.

          (r) Waiving, refusing to enforce, amending, restating,  superseding or
     modifying  any of the  provisions  of  this  Agreement  or any  Transaction
     Document, including, without limitation, the Collocation Agreement.

          (s) Taking any other  action  which,  by the terms of this  Agreement,
     requires  the  approval  or consent of not less than  seventy-five  percent
     (75%) of the Members.

          (t) Except as  expressly  set forth in the  Collocation  Agreement  or
     Section 9.12 of the Contribution  Agreement,  allocating to the Company any
     costs or expenses that are paid or incurred by any Member or its affiliates
     (excluding  the Company),  or paid by the Company but  reimbursable  by any
     Member or its affiliates (excluding the Company), in each instance.

          (u) With respect to the business and  operations of Newco II conducted
     or to be conducted  at or near the  location of 4800 N. 22nd St.,  Phoenix,
     Arizona,  waiving,   amending,   supplementing  or  modifying  any  of  the
     professional  fees,  facility fees or fee  allocations  by Newco II, to the
     extent such amounts or allocations were utilized in preparing the pro forma
     financial statements of Newco II attached to the Collocation Agreement.

          (v) With respect to the business and  operations of Newco II conducted
     or to be  conducted  at any  other  future  office  or  business  locations
     (including  without  limitation,  the office  located at 555 E. River Road,
     Tucson,  Arizona),  adopting any  professional  fees,  facility fees or fee
     allocations.

         Any of the  above  stated  actions  taken by the  Company  without  the
necessary manager approval is void ab initio.

         Section 8.10.  Committees.  The Managers  may, by resolution  passed by
eighty percent (80%) of the Managers,  designate  committees,  each committee to
consist  of two or more  Managers  (at  least  one of  which  must be a  Manager
designee of Prime and one of which must be a Manager  designee  of BDEC),  which
committees  shall have such power and authority and shall perform such functions
as may be provided in such  resolution.  Such committee or committees shall have
such name or names as may be  designated  by the Managers and shall keep regular
minutes of their proceedings and report the same to the Managers when required.

          Section  8.11.  Compensation  of Managers.  The Members,  by unanimous
     approval,  shall have the  authority to provide that any one or more of the
     Managers shall not be compensated,  and may, by unanimous approval, fix any
     compensation  (which may include  expenses) they elect to pay to any one or
     more of the Managers. ------------------------

          Section  8.12.  Action by  Written  Consent.  Any action  required  or
     permitted  to be taken at any meeting of the  Managers or of any  committee
     designated  by the  Managers  may be taken  without  a meeting  if  written
     consent,  setting forth the action so taken,  is signed by all the Managers
     or of such committee, and such consent shall have the same force and effect
     as a unanimous vote at a meeting. -------------------------

         Section 8.13. Meetings by Conference Telephone.  Managers or members of
any committee  designated by the Managers may  participate in and hold a meeting
of the Managers or such  committee by means of  conference  telephone or similar
communications  equipment  by means of which all  persons  participating  in the
meeting  can  hear  each  other,  and  participation  in  such a  meeting  shall
constitute   presence  in  person  at  such  meeting,   except  where  a  person
participates  in the  meeting  for  the  express  purpose  of  objecting  to the
transaction  of any  business  on the ground  that the  meeting is not  lawfully
called or convened.

          Section 8.14.  Liability of Managers.  No Manager of the Company shall
     be personally  liable for any debts,  liabilities,  or  obligations  of the
     Company,  including  under a  judgment,  decree,  or  order  of the  court.
     ---------------------

          Section 8.15. Specific Power of Managers.  The Managers shall have the
     authority  to enter into and  execute  all  documents  in  relation  to the
     formation  of the Company  including,  but not limited to,  issuance of the
     Certificate  of Formation  and this Limited  Liability  Company  Agreement.
     --------------------------

                                                    ARTICLE IX.
                                                      NOTICES

         Section 9.1. Form of Notice.  Whenever under the provisions of the Act,
the Certificate of Formation or this Limited  Liability Company Agreement notice
is required to be given to any Manager or Member, and no provision is made as to
how such notice shall be given,  notice shall not be construed to mean  personal
notice only, but any such notice may also be given in writing,  by mail, postage
prepaid,  addressed  to such Manager or Member at such address as appears on the
books of the Company, or by telecopy, telegraph or mailgram. Any notice required
or  permitted  to be given by mail  shall be deemed  to be given  three (3) days
after it is deposited, postage prepaid, in the United States mail as aforesaid.

          Section  9.2.  Waiver.  Whenever any notice is required to be given to
     any Manager or Member of the Company  under the  provision  of the Act, the
     Certificate of Formation or this Limited  Liability  Company  Agreement,  a
     waiver thereof in writing signed by the person or persons  entitled to such
     notice,  whether  signed  before or after the time  stated in such  waiver,
     shall be deemed equivalent to the giving of such notice. ------

                                                    ARTICLE X.
                                                     OFFICERS


         Any Manager may also serve as an officer of the  Company.  The Managers
may  designate  one or more persons who are not Managers of the Company to serve
as officers and may designate the titles of all officers.  The initial  officers
of the Company shall be: Ken Shifrin,  Chairman of the Board; Joe Jenkins, M.D.,
President;  Cheryl  Williams,  Vice  President,  Secretary  and Chief  Financial
Officer;  and Mark Rosenberg,  Vice President.  Unless  otherwise  provided in a
resolution of the Members or Managers the officers of the Company shall have the
powers  designated  with  respect to such  offices  under the  Delaware  Limited
Liability Company Act, and any successor statute, as amended from time-to-time.

                                                    ARTICLE XI.
                                                     INDEMNITY

         Section 11.1.  Indemnification.  The Company shall indemnify any person
who was or is a party or is  threatened  to be made a party  to any  threatened,
pending or  completed  action,  suit or  proceeding,  whether  civil,  criminal,
administrative, arbitrative or investigative, any appeal in such an action, suit
or  proceeding  and any  inquiry  or  investigation  that  could lead to such an
action,  suit or proceeding  (whether or not by or in the right of the Company),
by reason of the fact that such person is or was a manager, officer, employee or
agent of the  Company or is or was  serving at the  request of the  Company as a
director,  manager, officer, partner, venturer,  proprietor,  trustee, employee,
agent or similar  functionary  of another  corporation,  employee  benefit plan,
other enterprise,  or other entity, against all judgments,  penalties (including
excise and similar taxes), fines, settlements and reasonable expenses (including
attorneys'  fees and court  costs)  actually and  reasonably  incurred by him in
connection with such action,  suit or proceeding to the fullest extent permitted
by any  applicable  law,  and such  indemnity  shall inure to the benefit of the
heirs,  executors and administrators of any such person so indemnified  pursuant
to this Article XI. The right to indemnification  under this Article XI shall be
a contract  right and shall not be deemed  exclusive of any other right to which
those seeking  indemnification may be entitled under any law, bylaw,  agreement,
vote of members or disinterested managers or otherwise, both as to action in his
official  capacity  and as to action in  another  capacity  while  holding  such
office.  Any repeal or amendment of this Article XI by the Managers (pursuant to
Section  8.9  hereof)  or by  changes in  applicable  law  shall,  to the extent
permitted by applicable law, be prospective only, and shall not adversely affect
the  indemnification  of any person who may be  indemnified  at the time of such
repeal or amendment.

          Section   11.2.   Indemnification   Not   Exclusive.   The  rights  of
     indemnification and reimbursement provided for in this Article XI shall not
     be deemed exclusive of any other rights to which any such Manager, officer,
     employee or agent may be entitled under the Certificate of Formation,  this
     Limited Liability Company Agreement,  agreement or vote of Members, or as a
     matter of law or otherwise. -----------------------------

         Section  11.3.  Other  Indemnification  Clauses.   Notwithstanding  the
foregoing,   this  Article  XI  shall  not  be  construed  to   contradict   the
indemnification   provision  of  the  Contribution  Agreement.   Notwithstanding
anything  contained  herein,  this Article XI shall be ineffectual and shall not
permit or require  indemnification for all, or any, losses, costs,  liabilities,
claims or expenses arising, directly or indirectly,  from any action or omission
permitting or requiring indemnification under the Contribution Agreement; and in
no event may any  indemnity be allowed  under this  Agreement or pursuant to any
provision   of  the  Act  for  an  amount  paid  or  payable   pursuant  to  the
indemnification provisions of the Contribution Agreement.

                                                   ARTICLE XII.
                                                   MISCELLANEOUS

          Section  12.1.  Fiscal Year.  The fiscal year of the Company  shall be
     fixed by resolution of the Managers. -----------

          Section  12.2.  Records.  At the expense of the Company,  the Managers
     shall maintain records and accounts of all operations of the Company.  At a
     minimum,  the Company  shall keep at its  principal  place of business  the
     following records: -------

          (a) A current list of the name and last known mailing  address of each
     Member;
                  (b)      A current list of each Member's Membership Interest;

          (c) A copy of the  Certificate  of  Formation  and  Limited  Liability
     Company Agreement of the Company, and all amendments thereto, together with
     executed copies of any powers of attorney;

                  (d) Copies of the Federal, state, and local income tax returns
and reports for the Company's six most recent tax years; and

                  (e) Correct and  complete  books and records of account of the
Company.

          Section  12.3.  Seal.  The Company may by  resolution  of the Managers
     adopt  and  have a seal,  and  said  seal  may be used by  causing  it or a
     facsimile  thereof to be impressed or affixed or in any manner  reproduced.
     Any officer of the Company  shall have  authority  to affix the seal to any
     document requiring it. ----

          Section  12.4.  Agents.  Every  Manager and Officer is an agent of the
     Company for the purpose of the  business.  The act of a Manager or Officer,
     including  the execution in the name of the Company of any  instrument  for
     carrying  on in the  usual  way the  business  of the  Company,  binds  the
     Company. ------

         Section 12.5. Checks. All checks,  drafts and orders for the payment of
money,  notes  and other  evidences  of  indebtedness  issued in the name of the
Company  shall be  signed  by such  officer,  officers,  agent or  agents of the
Company  and in such  manner  as  shall  from  time to  time  be  determined  by
resolution of the Managers. In the absence of such determination by the Mangers,
such  instruments  shall  be  signed  by  the  Treasurer  or the  Secretary  and
countersigned  by the  President  or a Vice  President  of the  Company,  if the
Company has such officers.

          Section  12.6.  Deposits.  All funds of the Company shall be deposited
     from  time  to time to the  credit  of the  Company  in such  banks,  trust
     companies or other depositories as the Managers may select. --------

          Section 12.7.  Annual  Statement.  The Managers  shall present at each
     annual meeting a full and clear  statement of the business and condition of
     the Company. ----------------

         Section 12.8.  Financial  Statements.  As soon as practicable after the
end of each fiscal year of the  Company,  a balance  sheet as at the end of such
fiscal year,  and a profit and loss  statement  for the period  ended,  shall be
distributed  to the  Members,  along with such tax  information  (including  all
information  returns) as may be necessary for the  preparation of each Member of
its Federal,  state and local income tax returns.  The balance  sheet and profit
and loss statement  referred to in the previous  sentence may be as shown on the
Company's federal income tax return.

          Section 12.9. Binding Arbitration. Any controversy between the parties
     regarding  this  Agreement and any claims  arising out of this Agreement or
     its  breach  shall  be  submitted  to  arbitration  by  either  party.  The
     arbitration  proceedings shall be conducted by a single arbitrator pursuant
     to  the   Commercial   Arbitration   Rules  of  the  American   Arbitration
     Association.  The arbitration  shall be conducted in Dallas,  Texas and the
     arbitrator   shall   have   the   right  to  award   actual   damages   and
     -------------------  attorney fees and costs,  but shall not have the right
     to award punitive, exemplary or consequential damages against either party.

                                  ARTICLE XIII.
                                   AMENDMENTS

          Section 13.1.  Amendments.  This Agreement may be altered,  amended or
     repealed and a new limited liability company agreement may be adopted, only
     in  accordance  with the  provisions  of Section 8.9, but  otherwise at any
     regular  meeting or at any special  meeting called for that purpose,  or by
     execution of a written consent in accordance with the provisions of Section
     3.8. ----------

          Section 13.2. When Limited  Liability  Company Agreement Silent. It is
     expressly  recognized that when the Limited  Liability Company Agreement is
     silent or in conflict with the  requirements of the Act as to the manner of
     performing any Company  function,  the provisions of the Act shall control.
     -----------------------------------------------

                                             [Signature page follows]




<PAGE>


                                                 SIGNATURE PAGE TO
                                        LIMITED LIABILITY COMPANY AGREEMENT

         IN WITNESS WHEREOF,  the undersigned  Members hereby adopt this Limited
Liability  Company  Agreement as the Limited  Liability Company Agreement of the
Company, effective as of the 1st day of September, 1999.


                                          Barnet Dulaney Eye Center, P.L.L.C.


                                             By: /s/ Ronald W. Barnet, M.D.
                                                Ronald W. Barnet, M.D., manager

                                             By:/s/ David D. Dulaney, M.D.
                                                 David D. Dulaney, M.D., manager




                                          Prime Medical Operating, Inc.

                                            By: /s/ Cheryl Williams
                                            Printed Name: Cheryl Williams
                                            Title: Treasurer



<PAGE>



                                                     EXHIBIT A
                                                OWNERSHIP INTERESTS

Name                                                      Ownership Percentage

Prime                                                              60%

BDEC                                                               40%






<PAGE>