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                                                                EXHIBIT 10(jj)
    

                      NATIONAL MEDICAL REVIEW OFFICES, INC.

                                                                 CONFIDENTIAL

July 18, 1997

Robert Stutman, Chief Executive Officer
Substance Abuse Technologies, Inc.
4517 N.W. 31st Avenue
Ft. Lauderdale, Florida  33309

Re:      Letter of Agreement re Affiliation and Acquisition

Dear Robert:

On behalf of National Medical Review Offices, Inc. ("NMRO"), we are pleased to
submit for your review and signature, this letter of agreement (the "Letter"),
between NMRO and Substance Abuse Technologies, Inc. ("SAT"), which describes
the terms of our understanding and agreement regarding our affiliation in
connection with the acquisition by SAT from NMRO, its successors or assigns
(the "SAT Acquisition"), of certain assets of DataMed International ("DMI"), a
division of Global Med Technologies, Inc. ("GMTI").


As you are aware, NMRO has entered into a letter of intent with GMTI dated June
20, 1997 (the "GMTI Letter"), which describes the terms of the proposed
acquisition by NMRO from GMTI of certain DMI assets (the "NMRO Acquisition").
The purpose of this Letter is to memorialize our agreement on the material terms
of the SAT Acquisition, which are set forth in the Term Sheet that is attached
to and forms a part of this Letter. In order to be sure that we all understand
and agree upon the basic terms of the SAT Acquisition, we ask that you carefully
review the Term Sheet. The ultimate success of our agreements will require that
certain other commitments also be made, including the following:

1.       Exclusive Dealing.  SAT acknowledges that NMRO has expended 
         substantial sums of time and money in connection with legal,
         accounting, financial, and due diligence work performed in conjunction
         with the NMRO Acquisition.  Accordingly, for purposes of inducing NMRO 
         to execute this Letter, SAT agrees that during the period of ninety
         (90) days from the effective date of this Letter (i.e., the date of
         your execution of this Letter)(for purposes of this letter, we will
         refer to the this ninety day period as the "Exclusive Dealing
         Period"), SAT will not, and will not permit any of its agents or
         employees to, directly or indirectly, initiate, encourage or hold
         discussions or negotiations with, or submit or accept the submission
         of any offers or proposals from, or provide any nonpublic information
         to, any person or entity other than NMRO with respect to any
         affiliation or arrangement similar to those arrangements described in
         this Letter, or any 


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         purchase or lease of all or a material part of the assets or business
         of DMI, whether by sale of assets, capital stock, merger or
         consolidation, or otherwise, without the prior written consent of
         NMRO, which consent NMRO may give or withhold in its sole discretion. 
         Without limiting the generality of the foregoing, SAT agrees to revoke
         expressly any previous offer it may have made to GMTI regarding the
         purchase of DMI, or any asset of DMI.  SAT further agrees during the
         Exclusive Dealing Period to promptly notify NMRO of, and also to
         immediately reject, any proposal or offer that it may receive within
         the scope of the foregoing exclusivity requirements. Notwithstanding
         any of the foregoing provisions of this paragraph 1, NMRO agrees that
         SAT shall be relieved of any further, executory obligations under this
         paragraph 1, effective upon the occurrence of any of the following: 
         (i) on or before 5:00 p.m. (Pacific Time) on Friday, July 11, 1997,
         NMRO notifies GMTI of NMRO's election not to proceed with the NMRO
         Acquisition; or (ii) NMRO defaults in the performance of any material
         obligation under this Letter, and such default continues uncured for a
         period of ten (10) days following the receipt by NMRO from SAT of
         written notice specifying any such default with particularity; or
         (iii) NMRO defaults in the performance of any material obligation
         under the GMTI Letter, and such default continues uncured and
         uncontested by NMRO for a period of two (2) business days following
         the receipt by NMRO from GMTI of written notice specifying any such
         default with particularity.

2.       Due Authorization.  SAT represents and warrants that (i) all 
         approvals, authorizations, and actions or orders required of SAT for
         the authorization, execution and delivery of this Letter, and for the  
         consummation of the SAT Acquisition contemplated by this Letter have
         been obtained, and (ii) the execution and delivery of this Letter by
         SAT, and the execution and delivery by SAT of the definitive
         agreements contemplated by this Letter, do not and will not conflict
         with or violate any contract to which SAT is a party.  NMRO represents
         and warrants that (i) all approvals, authorizations, and actions or
         orders required of NMRO for the authorization, execution and delivery
         of this Letter, and for the consummation of the SAT Acquisition
         contemplated by this Letter have been obtained, and (ii) the execution
         and delivery of this Letter by NMRO, and the execution and delivery by
         NMRO of the definitive agreements contemplated by this Letter, do not
         and will not conflict with or violate any contract to which NMRO is a
         party.

3.       Business in the Ordinary Course. During the Exclusive Dealing Period,
         SAT agrees to operate its business only in the usual, regular and
         ordinary course consistent with past practices. During the Exclusive
         Dealing Period, NMRO agrees to operate its business only in the usual,
         regular and ordinary course consistent with past practices.

4.       Safeguarding Confidential Information.  Each party agrees not to 
         disclose any confidential documents and information provided by the
         other party pursuant to this Letter (the "Confidential Information"),
         except as follows:  (i) each party may disclose Confidential
         Information when required by law to do so; (ii) each party may
         disclose Confidential Information to its legal and financial
         consultants, and employees for purposes of reviewing the proposed SAT
         Acquisition; and (iii) Confidential Information does not include any
         document or information which:  (a) is, or hereafter becomes,
         generally available to the public other than as a result of a
         disclosure by a party, (b) was available to a party on a
         non-confidential basis prior to such party's receipt thereof pursuant
         to this 


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         Letter, or (c) becomes available to a party on a non-confidential
         basis from a source other than the other party.  If this Agreement
         terminates prior to completion of the SAT Acquisition, then each party
         agrees to promptly return to the other party the originals and
         all copies of any Confidential Information received from the other
         party pursuant to this Letter.

5.       Confidentiality of Acquisition.  SAT and NMRO and their respective 
         representatives agree to keep this Letter, the Acquisition and the
         matters contemplated herein confidential, except for disclosures that
         are required by law, that receive the prior written consent of the
         other party, or that are made by a party to its employees,
         attorneys and financial advisors for purposes of reviewing the
         proposed SAT Acquisition.  NMRO and SAT agree not to make any public
         pronouncement regarding the transactions contemplated herein without
         the prior written consent of the other, except to the extent required
         by law.  For purposes of this paragraph, "public pronouncement" means
         any statement, however communicated, intended for general
         dissemination, including any press release, but does not include
         materials used in connection with the filing with a regulatory body
         (including the Secretary of State and federal and state securities
         regulators) or any statement made for the legitimate business purposes
         of the maker, intended for the internal use of the maker and not
         likely to become available to the general public or any segment
         thereof.

6.       Cooperation.  SAT and NMRO each agree to cooperate with the other, 
         and to execute such other documents and take such other actions as may
         be reasonably necessary or desirable, in order to effect the   
         transactions contemplated by this Letter.  Without limiting the
         generality of the foregoing, SAT and NMRO agree to the following:  (i)
         the parties agree to coordinate all communications with GMTI regarding
         the SAT Acquisition and the transactions contemplated herein; (ii)
         each party agrees not to enter into any agreement with GMTI that is
         binding on the other party, except with the prior written consent of
         the other party; (iii) each party agrees to provide to the other, and
         its representatives, with any and all information and records relating
         to its business, properties and personnel, as may be reasonably
         necessary and appropriate in connection with the NMRO Acquisition and
         the SAT Acquisition; and (iv) each party agrees to cause its
         accountants and financial advisors to cooperate with the other in
         making available all such financial and tax information requested.

7.       Expenses.  SAT and NMRO agree that fees and out-of-pocket expenses 
         incurred by NMRO, including fees of NMRO's agents, advisers,
         attorneys and accountants, with respect to the negotiation of this
         Letter and the preparation and negotiation of definitive agreements
         contemplated by this Letter (collectively, the "Transaction Costs"),
         shall be paid and discharged in accordance with the following:  (i)
         SAT agrees to pay and discharge fifty percent (50%) of the Transaction
         Costs incurred by NMRO during the period from and including June 20,
         1997, through and including July 10, 1997; and (ii) if SAT does not
         make any election in accordance with paragraph 8 below, then SAT
         agrees to pay and discharge one hundred percent (100%) of the
         Transaction Costs incurred by NMRO during the period from and
         including July 11, 1997, through and including the closing of the SAT
         Acquisition.  SAT shall be obligated to pay and discharge the
         foregoing Transaction Costs within thirty (30) days of NMRO's delivery
         of reasonable documentation thereof.


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8.       Conditions to Closing of SAT Acquisition. SAT and NMRO agree that the
         obligations and commitments of the parties set forth in this Letter and
         the Term Sheet, are intended to create legally binding obligations
         between the parties. SAT and NMRO further agree that the consummation
         of the SAT Acquisition by the parties shall be subject to satisfaction
         of the following two (2) conditions precedent: (i) completion by SAT of
         its due diligence investigations of DMI prior to 5:00 p.m. (Mountain
         Time) on Thursday, July 10, 1997 (the "Due Diligence Deadline"); and
         (ii) the completion of the NMRO Acquisition.

9.       Survival of Certain Obligations. Except as set forth in paragraph 1,
         each party's obligations set forth in this Letter shall remain in full
         force and effect during the entire Exclusive Dealing Period, and shall
         survive the termination of this Letter, notwithstanding any failure by
         either party to complete the SAT Acquisition.

10.      Assignment.  SAT may not assign any rights or delegate any duties 
         hereunder without receiving the prior  written consent of NMRO, which
         consent NMRO may not unreasonably withhold.  Any sale, lease,
         assignment, merger or other transfer, in a single transaction or a
         series of transactions, of fifty percent (50%) or more of the assets,
         ownership, or membership interests of SAT, shall constitute an
         assignment that is subject to and prohibited by the provisions of this
         paragraph 10.  NMRO may not assign any rights or delegate any duties
         hereunder without receiving the prior written consent of SAT, which
         consent SAT may not unreasonably withhold.  Any assignment permitted
         hereunder shall be effective only if NMRO's or SAT's assignee agrees
         in writing to assume all of the assigning party's obligations and
         liabilities hereunder, and to be bound by all of the terms and
         conditions of this Letter, as it may be amended or supplemented from
         time to time.

If you wish to accept the proposal expressed in this Letter and the attached
Term Sheet, please so indicate by having an authorized SAT representative
countersign the enclosed duplicate copy and return it to NMRO, or its legal
counsel. This Letter may be signed in counterparts, and original signatures may
be transmitted by facsimile.

On behalf of NMRO, we would like to thank you for giving us an opportunity to
work with you in developing a mutually beneficial relationship. We encourage you
to contact us at any time if we can be of assistance.

Sincerely,

National Medical Review Offices, Inc.

By:

Its:


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Accepted and Agreed to:

Substance Abuse Technologies, Inc.

By:

Its:

Date:



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                                 TERM SHEET

                    NATIONAL MEDICAL REVIEW OFFICES, INC.

                     SUBSTANCE ABUSE TECHNOLOGIES, INC.

                               ACQUISITION OF

     DATAMED INTERNATIONAL, A DIVISION OF GLOBAL MED TECHNOLOGIES, INC.

I.       PURCHASE CONSIDERATION

         I.1      $1,600,000.00 payable in cash at closing
         I.2      Assumption of all obligations assumed in NMRO Acquisition

II.      INCLUDED ASSETS

         II.1     all DMI assets included in NMRO Acquisition
         II.2     except Excluded Assets

III.     EXCLUDED ASSETS

         III.1    all DMI assets excluded from NMRO Acquisition
         III.2    all trade names, trade marks, service names and services marks
                  used in connection with provision by DMI of medical review
                  officer services, including, without limitation, the use of
                  "National MRO" and "MRO" and similar names

IV.      ESCROW DEPOSIT

         IV.1     SAT to pay to NMRO on Monday, July 7, 1997, the sum of
                  $600,000.00, in exchange for assignment by NMRO of its rights
                  under the Escrow Agreement among GMTI, NMRO and Tri-State Bank
                  (the "Escrow Agreement")
         IV.2     deposit to be refundable on written instruction of SAT prior
                  to expiration of the Due Diligence Deadline, with such refund
                  to be made in accordance with the Escrow Agreement
         IV.3     deposit to be refundable on joint written instruction of SAT
                  and GMTI after the expiration of the Due Diligence Deadline,
                  in accordance with the Escrow Agreement
         IV.4     deposit to be held in interest bearing account, with interest
                  owned by SAT 
         IV.5     escrow agent fees paid by SAT up to $1,000; amount over 
                  $1,000 paid by GMTI 
         IV.6     deposit to be applied against purchase price at closing



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V.       DUE DILIGENCE

         V.1      SAT to complete all due diligence investigations of DMI prior
                  to Due Diligence Deadline 
         V.2      SAT to make best efforts to complete all due diligence as 
                  soon as reasonably practical, but in no event later than the 
                  Due Diligence Deadline;
         V.3      SAT to provide written notice to NMRO prior to the Due
                  Diligence Deadline, of SAT's election to proceed, or not to
                  proceed, with the SAT Acquisition

VI.      INTERIM MANAGEMENT AGREEMENT

         VI.1     SAT to assume operations of DMI as of June 30, 1997, pursuant
                  to an Interim Management Agreement until approval of the NMRO
                  Acquisition by the shareholders of GMTI, and the closing of
                  the NMRO Acquisition
         VI.2     Date of assumption of operations of DMI to be no later than
                  July 11, 1997 (with retroactive effect to June 30, 1997)
         VI.3     SAT to assume all DMI accounts receivable as of June 30,
                  1997, (represented by GMTI to be approximately $900,000.00)
         VI.4     SAT to assume all DMI accounts payable as of June 30, 1997,
                  (represented by GMTI to be approximately $410,000.00), and
                  accrued expenses (represented by GMTI to be approximately
                  $590,000.00)
         VI.5     SAT to assume all risk of losses incurred in operation of DMI,
                  except if the GMTI shareholders fail to approve NMRO
                  Acquisition

VII.     MRO SERVICES AGREEMENT

         VII.1    SAT to enter into exclusive MRO services agreement with NMRO
         VII.2    term of 5 years, with extension by mutual agreement
         VII.3    NMRO to be sole and exclusive provider of all MRO Services for
                  all SAT customers, subject to termination by SAT due to a
                  default by NMRO that remains uncured for thirty (30) days
                  after notice
         VII.4    MRO Services means and includes the services described in
                  addendum 1 attached hereto, including but not limited to,
                  receipt of all drug test results, processing, medical review,
                  and reporting of drug test results to SAT
         VII.5    drug test results include all positive and all negative 
                  results
         VII.6    all drug test results, including both positive and negative,
                  to be processed by NMRO, including any SAT customer election
                  for positive reports only, and fee applies to each and every
                  test, both positive and negative
         VII.7    SAT guarantees minimum volume of 400,000 tests per year,
                  beginning in calendar year 1998 
         VII.8    Fee for first 400,000 tests per year shall be $1.35 per test,
                  payable monthly 
         VII.9    Fee for each test in excess of 400,000 per year shall be 
                  $1.25 
         VII.10   during period covered by minimum volume guaranty, NMRO to 
                  bill and GMTI to pay minimum monthly amount of $45,000.00
         VII.11   all fees payable monthly with thirty (30) days of invoice


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         VII.12   Fee for review of positive screening test other than a
                  laboratory test (e.g., an on-site test), shall be NMRO's usual
                  and customary fee, but not less than $49, and subject to the
                  most competitive price covenant as set forth below
         VII.13   NMRO agrees to most competitive price covenant (most favored
                  nations clause) for its fees for substantially the same MRO
                  Services provided by NMRO to other TPAs, and other customers
                  (except for WAL MART and HSNA), for an initial period of 180
                  days, subject to: (i) SAT establishes computer interface and
                  download capability and provides direct customer service; (ii)
                  ultimate price to be based upon level/scope of service; (iii)
                  after first 180 days, the parties to renegotiate price based
                  on level/scope of service; and (iv) prices not to exceed $1.35
                  and $1.25 as set forth above
         VII.14   NMRO to perform all billing services when requested by SAT
         VII.15   NMRO to have the right to audit, at its expense, SAT books of
                  account and records relating to MRO Services and laboratory
                  services provided to SAT customers
         VII.16   NMRO to provide 1 non-physician FTE in Florida to support
                  local MRO services

VIII.    NON-COMPETITION AGREEMENT OF SAT

         VIII.1   SAT agrees that during the term of the MRO Services Agreement,
                  SAT shall not directly or indirectly, without the prior
                  written consent of NMRO, which consent may be withheld by NMRO
                  in its sole and absolute discretion, (i) own, operate or
                  establish, provide services for or on behalf of, or otherwise
                  engage or participate in, or (ii) assist any other person or
                  entity in owning, operating, establishing, providing services
                  for or on behalf of or engaging or participating in, any
                  business or activity which is, or will become, competitive
                  with any MRO Services provided by NMRO under the MRO Services
                  Agreement with SAT.

IX.      REFERRAL AND NON-SOLICITATION AGREEMENT OF NMRO

         IX.1     NMRO agrees that during the term of the MRO Services
                  Agreement, SAT shall be its primary referral source for
                  prospective customers seeking full consulting for substance
                  abuse in the workplace (including employer drug testing policy
                  development), and background screens.
         IX.2     NMRO agrees that during the term of the MRO Services
                  Agreement, NMRO shall not directly, without the prior
                  written consent of SAT, which consent may be withheld by SAT
                  in its sole and absolute discretion, solicit any then
                  existing or prospective SAT customer for the provision of any
                  of the following services, so long as such service continues
                  to be provided by SAT:  (i) full consulting for substance
                  abuse in the workplace (including employer drug testing
                  policy development), and (ii) background screens.  For
                  purposes of the foregoing, a person or entity shall be
                  considered to be a "prospective SAT customer" only if all of
                  the following apply:  (i) NMRO has received notice from SAT
                  in writing that such person or entity has become a
                  prospective purchaser of services from SAT; (ii) NMRO is not
                  already engaged in discussions with such person or entity;
                  and 

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                  (iii) SAT and such person or entity are actively engaged in
                  negotiations for the provision of services by SAT.

X.       COLLATERAL ASSIGNMENT

         X.1      SAT agrees to collaterally assign to NMRO all MRO Services
                  Agreements between SAT and DMI Customers, and all of SAT's
                  rights and obligations thereunder, effective upon termination
                  of the MRO Services Agreement between SAT and NMRO due to a
                  default by SAT in the performance of its payment obligations
                  or non-compete obligations, that remains uncured for thirty
                  (30) days after notice
         X.2      SAT agrees to use its best efforts to cause to be included in
                  each MRO Services Agreement between SAT and a DMI Customers, a
                  clause expressly permitting the assignment of such agreement
                  by SAT to NMRO
         X.3      assignment to be effective upon written notice from NMRO
                  following SAT's failure to cure a covered default within
                  thirty (30) days after notice
         X.4      assignment to be effective in addition to any other remedies
                  to which NMRO may be entitled as a result of SAT breach

XI       ADDITIONAL AGREEMENTS

         XI.1     Definitive agreements reflecting the SAT Acquisition will
                  include representations, warranties, conditions, and other
                  terms customary for transactions of this type


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