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                                    AGREEMENT

     This is an agreement (the  "Agreement"),  dated September 4, 1998,  between
Medical Technology Laboratories,  Inc. ("MTL"), Community Clinical Laboratories,
Inc.  ("CCL"),  James McKeown,  Sr. and James McKeown,  Jr. (the "McKeowns") and
Vincent Gepp ("Gepp").

                                   Background

     On August 4, 1998, the parties entered into the Asset Acquisition Agreement
(the  "Acquisition  Agreement"),  a copy of which is  attached  as Exhibit A, in
which MTL  agreed to  acquire  certain  assets of CCL.  In  Section  3(e) of the
Acquisition  Agreement,  CCL was  required  to decide  whether  MTL would act as
custodian  for  its  accounts  receivables  and  liabilities.  Pursuant  to this
provision of the Acquisition  Agreement,  CCL decided that it desired MTL to act
as the custodian of its accounts receivables and MTL agreed to act as custodian.
Accordingly,  in  consideration of the mutual covenants and agreements set forth
below, the parties agree as follows:

                                      Terms

     Appointment.  CCL desires to appoint MTL as the  custodian  of its accounts
receivables   and  MTL  agrees  to  act  as  the  custodian  of  CCL's  accounts
receivables.

     Duties.  MTL will use its  reasonable  efforts  to collect  CCL's  accounts
receivables and will use the proceeds of these  collection  efforts to pay CCL's
liabilities.  MTL will  provide an employee  experienced  in the  collection  of
accounts  receivable  for a minimum of 40 hours per week for a period of 90 days
beginning  August  31,  1998.  After the 90  day-period,  the  parties  agree to
negotiate  a new  agreement  to  provide  for  additional  services  that may be
required of MTL relating to the uncollected accounts receivables.

     Payment of Costs. CCL and the McKeowns agree that they will reimburse up to
$50,000 of the cost of  documented  postage  and  supplies.  This  reimbursement
amount will be deducted from the purchase  price payment as set forth in Section
3(a) of the Acquisition  Agreement;  provided,  however, that the maximum amount
that  may be used to  reduce  a  single  purchase  price  payment  to  reimburse
documented costs will be $25,000, beginning with the second payment in 1999.

     Term.  MTL  agrees  that it  will  continue  as the  custodian  under  this
Agreement until the earlier of: (a) the expiration of the Acquisition Agreement;
(b) the payment of the maximum  purchase price of $2,500,000;  or (c) the mutual
agreement of the parties to terminate this Agreement.

     Duties of Gepp. MTL appoints Gepp to negotiate with vendors,  receive funds
and make  disbursements  on behalf of CCL as directed by MTL.  CCL and MTL agree
that Gepp,  a consultant  for MTL, is  empowered to negotiate  the amounts to be
paid to  vendors  on the list,  attached  to this  Agreement  as  Exhibit B, and
prescribe a period within which vendors must make their payments.  Gepp must use
reasonable efforts to negotiate with the vendors.

     Gepp agrees that, if he is indicted, is convicted,  pleads guilty to, or is
formally charged with a "healthcare crime," whether a misdemeanor or felony, MTL
may  terminate  any  relationship  with  Gepp  and may  discontinue  any and all
payments  to Gepp that may be due under this  Agreement.  For  purposes  of this
section,  a  "healthcare  crime"  means any action  that  results in  exclusion,
whether  voluntary or involuntary,  of Gepp from any federal or state healthcare
program,  or otherwise  would  prohibit  Gepp from being  employed by or receive
payments from a company that participates in the Medicare or Medicaid program or
any other state or federal healthcare program.


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     Method of Payment to  Creditors.  Payments  to  creditors  pursuant to this
Agreement will be made first to secured creditors,  then to unsecured creditors,
unless  formally  directed  otherwise  by any  government  agency  or  court  of
competent jurisdiction.

     Liability.  Neither  Gepp,  MTL  nor any of its  affiliates,  stockholders,
officers,  employees  or agents  will be liable to CCL or the  McKeowns  for any
loss,  liability,  damage or expense  arising out of or in  connection  with the
performance  of  services  contemplated  by this  Agreement,  unless  such loss,
liability,  damage or  expense  is a result of the  willful  misconduct  of such
person.  CCL  agrees to  indemnify  and hold  harmless  MTL,  its  stockholders,
affiliates,  officers,  agents and employees  against and from any and all loss,
liability,  suits,  claims,  costs,  damages and expenses,  including reasonable
attorneys' fees, arising from MTL's performance under this Agreement,  except as
a result of the willful misconduct of the person in question.

     Independent  Contractor  Status.  MTL and CCL agree  that MTL will  perform
services under this Agreement as an independent  contractor,  retaining  control
over and  responsibility  for its own operations and personnel.  Neither MTL nor
its officers,  employees or agents will be considered employees or agents of CCL
as a result of this Agreement nor will any of them have authority to contract in
the name of or bind the  Company  by  reason  of this  Agreement,  except as the
parties may expressly agree in writing. Likewise, neither this Agreement nor any
conduct  under  this  Agreement  shall be  deemed to  create a  relationship  of
employer-employee, partnership, joint venture, or other common enterprise.

     General Provisions.

     Benefit and  Assignment.  This Agreement shall be binding upon and inure to
the benefit of the parties and their  respective  successors  and  assigns.  The
rights  of the  Seller  may not be  assigned.  The  rights  of the  Buyer may be
assigned to a  subsidiary  or  affiliate  of the Buyer,  provided  that any such
assignment   shall  in  no  way  relieve  the  Buyer  of  its   obligations  and
responsibilities under this Agreement.

     Governing Law. This Agreement  shall be governed by and construed under the
laws of the State of Florida.

     Notices. All notices,  requests, demands and other communications hereunder
shall be in writing, and shall be deemed to have been duly given if delivered by
overnight delivery service or hand delivered, addressed as follows:

                  If to the Buyer:

                           Medical Technology Laboratories, Inc.
                           12920 Automobile Boulevard
                           Clearwater, Florida 34622
                           Attn:  Mr. Todd E. Siegel, President

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                  With a copy to:

                           Holland & Knight LLP
                           400 North Ashley Drive
                           Suite 2300
                           Tampa, Florida  33602
                           Attn:  Robert J. Grammig, Esq.

                  If to the Seller:

                           Community Clinical Laboratories, Inc.
                           1375 South Fort Harrison Avenue
                           Clearwater, Florida 33756
                           Attn:  James L. McKeown, Jr.

                  With a copy to:

                           Conklin, Stanley & Probst, P.A.
                           1465 South Fort Harrison Avenue, #202
                           Clearwater, Florida 34616
                           Attn:  Paul Probst, Esq.

                  If to the Shareholders:

                           James L. McKeown, Sr.
                           430 West Druid Road
                           Clearwater, Florida 34616

                           and

                           James L. McKeown, Jr.
                           11410 74th Avenue North
                           Seminole, Florida 33772


     Expenses.  Except as otherwise provided in this Agreement,  any expenses in
connection  with  this  Agreement  or  the  transactions  contemplated  in  this
Agreement shall be paid for by the party incurring such expenses.

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

     Headings.  All  paragraph  headings are inserted for  convenience  only and
shall not modify or affect the construction or  interpretation  of any provision
of this Agreement.


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     Amendment,  Modification  and  Waiver.  This  Agreement  may  be  modified,
amended,  and  supplemented by mutual written  agreement of the parties,  at any
time prior to the Closing. Each party may waive any condition intended to be for
its benefit.  Each amendment,  modification,  supplement,  or waiver shall be in
writing executed by both parties.

     Entire  Agreement.  This Agreement  represents the entire agreement between
the parties and supersedes all prior  negotiations  and discussions by and among
the parties in connection with this Agreement or its subject matter.

     Disputes  Regarding  Purchase  Price.  In the event the Seller disputes any
calculation  of the Purchase Price made under this Agreement and the parties are
unable to resolve this dispute within thirty days, then each party shall appoint
(within thirty days) an independent certified public accountant to rule upon the
dispute.  If the two accountants  are unable to resolve the dispute,  they shall
appoint a third accountant,  who shall have the final,  nonappealable  authority
over  the  dispute.  The  accountants  shall  award  the  costs  of the  dispute
resolution as they deem appropriate. IN WITNESS WHEREOF, the parties hereto have
executed this Agreement on the date set forth above.

                                    BUYER:

                                    MEDICAL TECHNOLOGY LABORATORIES, INC.

                                    By:_______________________
                                    Name:  Todd E. Siegel
                                    Its:  President

                                    SELLER:

                                    COMMUNITY CLINICAL LABORATORIES, INC.

                                    By:_______________________
                                    Name:_____________________
                                    Its:______________________


                                    SHAREHOLDERS:
 
                                    __________________________
                                    James L. McKeown, Sr.
                              
                                    __________________________
                                    James L. McKeown, Jr.


                                    CONSULTANT:

                                    __________________________ 
                                    Vincent Gepp