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EXHIBIT 10.11

                    PRESCRIPTION BENEFIT MANAGEMENT AGREEMENT

         THIS PRESCRIPTION BENEFIT MANAGEMENT AGREEMENT ("Agreement") is made by
and between PROVANTAGE HEALTH SERVICES, INC., a Delaware corporation, with its
principal place of business at N19 W24130 Riverwood Drive, Waukesha, Wisconsin
53188, hereinafter referred to as "PROVANTAGE", and AMERICAN MEDICAL SECURITY
HOLDINGS, INC., a Wisconsin corporation ("Holdings") and its present and future
wholly-owned insurance company subsidiaries with active business (which as of
the date hereof includes United Wisconsin Life Insurance Company, a Wisconsin
insurance company, ("UWLIC") Unity HMO of Illinois, Inc., an Illinois health
maintenance organization ("Unity) and American Medical Security Health Plan,
Inc. d/b/a American Medical Healthcare, a Florida health maintenance
organization ("AMH") with their principal places of business at 3100 AMS
Boulevard, Green Bay, Wisconsin 54313, Holdings, UWLIC, Unity and AMH
hereinafter collectively referred to as "AMS."

         WHEREAS, AMS has adopted various prescription drug programs referenced
on EXHIBIT A attached hereto (the "Plans") for various clients' eligible
employees and their eligible dependents (the "Plan Participants"). A description
of each Plan (the "Plan Parameters") will be communicated by AMS to PROVANTAGE
either electronically or in written hard copy format prior to the effective date
of this Agreement. Additional Plans may be added to EXHIBIT A from time to time
during the term of this Agreement. Such additions shall be evidenced by a
written Addendum to this Agreement which is signed by AMS and PROVANTAGE. The
Plan Parameters of any such additional Plans shall be communicated to PROVANTAGE
prior to the effective date thereof.

         WHEREAS, PROVANTAGE is a prescription benefit manager, and maintains a
computerized claims processing system, a prescription drug mail service, and a
network of retail pharmacies (the "Participating Pharmacies") who have agreed to
provide prescription services for PROVANTAGE's clients including AMS, and

         WHEREAS, additional information with respect to AMS and the Plans is
set forth on the AMS Data Sheet attached to this Agreement as EXHIBIT B (the
"Data Sheet"); and

         WHEREAS, PROVANTAGE and AMS' affiliate, American Medical Security, Inc.
("AMS, Inc."), have entered into that certain Prescription Benefit Management
Agreement dated June 28, 1995 (the "1995 Agreement"), whereby PROVANTAGE has
agreed to provide prescription benefit management services to AMS upon the terms
and conditions set forth herein; and

          WHEREAS, PROVANTAGE and AMS, Inc. amended the 1995 Agreement pursuant
to the First Amended and Restated Prescription Benefit Management Agreement
dated March 16, 1996 (the "1996 Agreement"); and

         WHEREAS, PROVANTAGE and AMS desire to terminate the 1996 Agreement and
enter into the following agreement for the provision of Prescription Benefit
Management services, effective January 1, 2000; and

         WHEREAS, PROVANTAGE and AMS have agreed to enter into the following
agreement.

                             I. GENERAL APPOINTMENT

1. PROVANTAGE shall be AMS' exclusive prescription benefit manager with respect
to the Plans during the Initial Term (as hereinafter defined), provided, however
that such exclusivity shall not apply to business that is acquired by AMS as a
result of an acquisition of another companies' stock, assets or block of
business, through reinsurance or otherwise (the "Acquired Business") so long as
AMS uses its
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good faith, diligent and commercially reasonable efforts to transition such
prescription business to PROVANTAGE as soon as reasonably possible, including
exercising any termination rights at the earliest possible time without
incurring any material financial penalty. As the prescription benefit manager of
the Plans, PROVANTAGE shall diligently assist AMS in establishing and
implementing prescription benefit management programs designed to lower the
total cost of Plan Participants' health care. Toward this end, PROVANTAGE shall
manage all prescription claim processes for AMS by implementing an optimal mix
of cost reduction strategies which may include, but are not limited to:

          - Programs designed to increase mail service utilization;
          - Formulary management services;
          - Drug utilization evaluation programs, including:
               - Drug utilization review programs (prospective, concurrent and
                 retrospective)
               - Educational programs (as such programs may be developed by
                 PROVANTAGE from time to time)
               - Disease state management processes (as such processes may be
                 jointly developed by PROVANTAGE and AMS from time to time)

PROVANTAGE's services, which shall be provided subject to and in accordance with
the terms and conditions of this Agreement, shall initially be prescription
claims processing, prescription drug mail services, and formulary management
services described in this Agreement, and shall include such other functions as
may be mutually agreed upon in writing by AMS and PROVANTAGE from time to time
during the term of this Agreement. AMS and PROVANTAGE agree to work together in
good faith to develop and implement mutually acceptable programs, procedures and
policies to more effectively and efficiently manage the prescription benefits
available to Participants under the Plans.

                       II. PRESCRIPTION CLAIMS PROCESSING

2. APPOINTMENT. Except as provided herein, AMS hereby appoints PROVANTAGE as its
exclusive Prescription Claims Processor during the Initial Term for all existing
and new business written pursuant to the Plans, and PROVANTAGE hereby accepts
such appointment.

3. AUTHORITY. PROVANTAGE hereby agrees to perform all of the following claims
processing functions with respect to the Plans, and AMS hereby grants PROVANTAGE
the authority and empowers PROVANTAGE to perform such functions:

          A.   To process all claims received from Participating Pharmacies
               and/or eligible Plan Participants in accordance with the Plan
               Parameters and this Agreement;

          B.   To reject or otherwise deny claims which are incomplete,
               ineligible, outside the dates specified by this Agreement or
               invalid for any other reason;

          C.   To issue checks to Participating Pharmacies for the payment of
               claims;

          D.   To issue checks directly to Plan Participants for covered items
               under the Plans if they are unable to have a Participating
               Pharmacy submit the claims on their behalf at the retail and mail
               reimbursement rates set forth herein;

          E.   To audit Participating Pharmacies as deemed necessary or
               appropriate by PROVANTAGE for compliance with the specific Plan
               parameters as well as for fraudulent or incorrectly submitted
               claims;

          F.   To generate reports for AMS, Participating Pharmacies and for
               PROVANTAGE's own uses;

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          G.   To maintain hard copy and/or computerized records of all
               transactions completed hereunder for a reasonable period of time
               as may be required by law;

          H.   To adjust the amount paid on a submitted claim so that it
               accurately reflects:
               i.     The correct ingredient cost at the time the benefit was
                      received as determined by First Data Bank current drug
                      pricing database.
               ii.    The correct dispensing fee, if any.
               iii.   The correct sales tax, if any, for the State in which the
                      benefit was rendered.
               iv.    The correct deductible or copayment, if any, that should
                      have been collected.
               v.     To provide such other functions as may be indicated on the
                      Data Sheet.

          I.   To process prior authorizations to Plan Participants within an
               average of 24 hours once all information has been received for
               certain Pharmaceuticals (as hereinafter defined) where
               appropriate pursuant to the terms of the Plan Parameters.

If the processing of prior authorizations by PROVANTAGE exceeds the 24 hour
guarantee set forth in subsection I, above, PROVANTAGE shall pay AMS $500 for
each instance, up to a maximum annual penalty of $5,000.

Any error by PROVANTAGE in claims processing or administration will result in
PROVANTAGE paying a financial penalty to AMS equal to the excess claim cost
incurred by Plan Participants. Additionally, PROVANTAGE guarantees that it will
have a 95% accuracy rate for claims processing and administration. Should the
processing of claims by PROVANTAGE fall below a 95% accuracy rate, PROVANTAGE
shall pay to AMS a penalty of $200 for each full percentage point that the
processing accuracy level is below the guaranteed level, up to a maximum annual
penalty of $5,000. In addition, if PROVANTAGE is below the 95% accuracy level,
PROVANTAGE shall also pay all reasonable costs incurred by AMS in auditing
PROVANTAGE's performance hereunder.

PROVANTAGE will also guarantee resolution of 95% of Plan Participant-submitted
claims within 35 days of receipt of the claim. It is understood that resolution
of the claims is dependent upon the timing of the receipt of the claims and the
next semi-monthly processing cycle. Based upon when the claim was received, the
payment or notice of denial will be mailed between five and 35 days of receipt.
PROVANTAGE's failure to meet this provision will result in PROVANTAGE paying AMS
a $500 penalty for each full day that the performance level is below the
guaranteed level up to a maximum annual penalty of $5,000. In addition,
PROVANTAGE guarantees that its claims processing system shall be available 99.5%
of the time (assuming 24 hours a day, 7 days a week) except for scheduled normal
system maintenance for which AMS has been notified; PROVANTAGE's failure to meet
such availability will result in a penalty of $1,000 per day up to a maximum
annual penalty of $5,000.

These penalties shall be in addition to any other rights, remedies or recoveries
AMS may have under this Agreement or available at law or in equity.

4.   IDENTIFICATION CARDS. AMS will issue identification cards for eligible Plan
Participants containing the following information:

         A.       AMS' NAME*
         B.       PARTICIPANT'S NAME*
         C.       PARTICIPANT'S IDENTIFICATION NUMBER*
         D.       GROUP NUMBER
         E.       CO-PAY (IF ANY)*
         F.       EFFECTIVE DATES OR THE WORDS "ON-LINE ELIGIBILITY"
         G.       SPECIAL NOTES PERTAINING TO THE PLAN (IF APPLICABLE)
         H.       PROVANTAGE NAME AND LOGO
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Each single Plan Participant will be issued one card. Each Plan Participant that
has dependent coverage will be issued two cards. If a card is lost or stolen,
AMS will issue a replacement card.

5.   PAYMENT OF CLAIMS. AMS assumes all financial responsibility and shall pay
for all reimbursable claims pursuant to the Plan Parameters submitted to
PROVANTAGE, whether by Participating Pharmacies or Plan Participants. AMS
further acknowledges the right of any Participating Pharmacy to proceed directly
against AMS to collect any legitimate claim which AMS has failed to pay to the
Participating Pharmacy through PROVANTAGE. This is a waiver of any claim of lack
of privity of contract between AMS and the Participating Pharmacy.

AMS shall transfer funds for the payment of valid prescription drug claims under
the Plan to PROVANTAGE pursuant to the banking arrangement between the parties
as specified in this Agreement.

6.   DRUG COST CALCULATION. PROVANTAGE shall use prescription drug pricing
information and clinical databases supplied by First Data Bank, or any other
nationally recognized database. AMS agrees to hold PROVANTAGE harmless from
liability for any claim or payment arising out of inaccurate information
supplied to and used by PROVANTAGE in good faith.

7.   DRUG UTILIZATION REVIEW (DUR). PROVANTAGE shall, as part of the electronic
claim adjudication process, perform Drug Utilization Review (DUR). DUR includes
drug interaction screening and other informational messages. The information
generated and provided in connection with DUR is intended as a supplement to,
and not a substitute for, the knowledge, expertise, skill, and judgment of
physicians, pharmacists and other health care providers. PROVANTAGE disclaims
all responsibility for any and all actions or interventions, taken or not taken
as a result of providing this information. AMS understands and authorizes
PROVANTAGE to inform providers that the information provided should not be
relied upon as a substitute for their professional judgment and AMS acknowledges
that DUR shall not prevent providers from dispensing prescriptions or providing
other goods and services in opposition to the information they receive under
PROVANTAGE's DUR Program. Providers are individually responsible for acting or
not acting upon the information provided through PROVANTAGE's DUR Program, and
for performing services in each jurisdiction consistent with the scope of their
professional licenses.

PROVANTAGE relies upon outside databases and software provided by other vendors
to provide information used by PROVANTAGE in its DUR Program. PROVANTAGE's
performance is limited by the information sought and received by and from these
vendors. PROVANTAGE will attempt to update these databases on a reasonable basis
to reflect changes in the standards of pharmaceutical prescribing, however, no
database will contain all currently available information. In most cases the
vendors limit or exclude warranties regarding the information provided to
PROVANTAGE for use in its DUR Program. Such limitations and exclusions shall be
communicated by PROVANTAGE to AMS, and after such communication, shall be
incorporated herein by this reference.

Further, PROVANTAGE may not have all the relevant information necessary for the
purposes of providing DUR information including, but is not limited to, patient
diagnoses, utilization of drugs obtained without using PROVANTAGE's claims
processing system or not included in the patient's active profile, patient's
medical history, and any other idiosyncrasies of a patient. PROVANTAGE shall
have no obligation to acquire information concerning any patient where
sufficient information is at any time unavailable to enable PROVANTAGE's DUR
Program to determine whether or not intervention is indicated.

PROVANTAGE's DUR Program is dependent upon the accurate transmission and
processing of data by electronic means. AMS agrees to hold PROVANTAGE harmless
from liability for any intervention or non-intervention resulting from any
interruption in the electronic processing regardless of the reason for said
interruption, except if PROVANTAGE is directly responsible for said
interruption. Because of the large number of computer systems and software in
use by providers, PROVANTAGE cannot and does not guarantee that a provider is
technically capable of receiving DUR information.
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Except as provided herein, PROVANTAGE disclaims all express and implied
warranties of any kind, including but not limited to, any warranty as to the
quality, accuracy or suitability for any particular purpose of the information
generated and provided through DUR. PROVANTAGE disclaims any liability for
consequential, incidental, exemplary, punitive or special damages incurred
directly or indirectly in connection with PROVANTAGE's performance of or
omission to perform, DUR services or resulting from reliance on or use of
information furnished under PROVANTAGE's DUR program.

8.   REPORTS AND STATEMENTS. PROVANTAGE shall provide AMS with a detailed report
on all claims paid or rejected on its behalf. In addition PROVANTAGE shall
provide a claim tape to AMS within seven business days following the end of a
payment cycle. PROVANTAGE shall provide all standard management reports to AMS
within 15 calendar days from the end of any relevant reporting period.
PROVANTAGE shall pay to AMS $250 per business day for each claim tape or batch
of reports that is not delivered within the number of days guaranteed, up to a
maximum annual penalty of $5,000. This penalty shall be in addition to any other
rights, remedies or recoveries AMS may have under this Agreement or available at
law or in equity.

AMS shall be permitted to review at PROVANTAGE's premises the quarterly reports
generated and maintained by PROVANTAGE evidencing PROVANTAGE's performance under
this Agreement with respect to the various performance guarantees set forth
herein.

PROVANTAGE shall provide all Participating Pharmacies which submit claims for
reimbursement with a remittance report.

9.   AUDIT. PROVANTAGE will perform audits of Plan Participants' claims or
Participating Pharmacies at its own discretion to ensure the integrity and
validity of the claims it receives and processes on behalf of AMS, provided,
however that PROVANTAGE guarantees (i) routine statistical audits of at least 2%
of the Participating Pharmacies on an annual basis, and (ii) if after a review
of statistical audit results, an on-site audit is justified, PROVANTAGE will
perform an on-site audit of 1% or more of Participating Pharmacies on an annual
basis. Should PROVANTAGE fail to perform the statistical or onsite audits of the
Participating Pharmacies in accordance with this Paragraph, PROVANTAGE shall pay
to AMS a penalty of $500 for each Participating Pharmacy that it did not audit,
up to an annual maximum penalty of $5,000. This penalty shall be in addition to
any other rights, remedies or recoveries AMS may have under this Agreement or
available at law or in equity.

AMS may receive copies of these summarized audits on an annual basis. In
addition, AMS can review all results of the audits on PROVANTAGE's premises upon
request and after providing advance notice. If PROVANTAGE finds grounds for
denying or charging back any claims AMS will be notified. In the event that an
audit of a Participating Pharmacy by PROVANTAGE results in additional funds due
to AMS, AMS shall receive 90% of such funds and PROVANTAGE shall retain 10%.

AMS may also request an audit of a specific claim or Participating Pharmacy, to
be conducted at AMS' expense. In the event that an audit of a Participating
Pharmacy by AMS results in additional funds due to AMS, AMS shall receive 100%
of such funds.

PROVANTAGE's own books and files will be available for AMS' inspection during
regular business hours. However, AMS may only inspect PROVANTAGE's books and
files as they pertain to AMS' Plans and PROVANTAGE's compliance with this
Agreement in accordance with ProVantage's External Account Audit Policy (the
"Policy"). While AMS agrees to follow all audit procedures in the Policy, in the
event there is a direct conflict between specific terms in this Agreement and
specific terms in the Policy relating to fees and scope of auditing, this
Agreement shall control.

In accordance with Section 3(A) above, PROVANTAGE agrees that 100% of the claims
that are administered and processed by PROVANTAGE will be in accordance with the
terms of the Plan Parameters and this Agreement including, but not limited to,
EXHIBIT B. AMS, at its own cost and
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expense, shall have the right to audit PROVANTAGE's books and records to ensure
compliance with this provision. If an outside auditing firm is utilized by AMS
to audit the accuracy of the claims administered and processed by PROVANTAGE
hereunder, PROVANTAGE shall share in the cost of such outside auditing firm
provided that PROVANTAGE has had input in the selection of such outside auditing
firm.

10.  COMPENSATION. AMS agrees to pay to PROVANTAGE such compensation as
indicated on the Data Sheet. PROVANTAGE will provide AMS an itemized monthly
bill. PROVANTAGE shall have the right after the initial term of this Agreement
to change the level of compensation PROVANTAGE receives hereunder upon sixty
(60) days written notice to AMS. AMS may object to any increase in such
compensation by giving written notice to PROVANTAGE at least thirty (30) days
prior to the expiration of the sixty (60) day period. In the event the parties
cannot agree on an appropriate level of compensation, this Agreement shall
terminate at the end of the sixty (60) day period or at such later date as may
be mutually agreed to by the parties.

11.  BILLING CYCLE AND PAYMENTS. AMS hereby authorizes PROVANTAGE to debit the
account indicated on the Data Sheet for prescription drug claims and other
charges authorized hereunder. Such debits shall be made via Automated Clearing
House ("ACH"). PROVANTAGE will bill AMS or AMS' designee on a semi-monthly basis
to enable payment of valid claims submitted to PROVANTAGE in a timely manner.
The first billing statement of every month will include charges for all claims
submitted by Participating Pharmacies and for all mail services rendered between
the first (1st) and the fifteenth (15th) of the month. The second billing
statement of every month will include charges for all claims submitted by
Participating Pharmacies and all mail services rendered between the sixteenth
(16th) and the last day of the month. The first billing statement of each month
will be mailed on the sixteenth (16th) of each month, or the first business day
thereafter. The second billing statement of each month will be mailed on the
first (1st) day of the following month, or the first business day thereafter.
AMS' account will be debited via ACH on the twenty second (22nd) of each month,
or the first business day thereafter, for the first monthly billing statement.
AMS' account will be debited via ACH on the seventh (7th) day of the following
month, or the first business day thereafter, for the second monthly billing
statement.

AMS warrants to PROVANTAGE that it shall make available for debit sufficient
funds to meet the full amount of each invoice submitted to AMS by PROVANTAGE.
All bills shall be deemed to have been received by AMS on the third (3rd) day
after the date said bill was mailed, or by the end of the next business day if
sent by facsimile or express mail. Payments more than 7 days past due shall be
subject to interest at the rate of one half of one percent per semi-monthly
billing period (twelve percent (12%) per annum) or the maximum portion thereof
allowed by law.

12.  OPTIONAL PROGRAMS. AMS may participate in any one or more of PROVANTAGE's
     Optional Programs, as described in the Plan Parameters.

13.  NEW STANDARD CLINICAL PROGRAMS. At no additional cost to AMS, PROVANTAGE
shall offer to AMS its new standard program offerings including (i) its
enhancements to formulary management services, (ii) drug conflict surveillance,
(iii) price parity, (iv) quantity/length of therapy edits, (v) non-clinical
prior authorization, (vi) utilization analysis/review and recommendations, (vii)
concurrent DUR. Such programs are further described in Section 2 of a certain
December 1, 1999 proposal by PROVANTAGE to AMS (the "Standard Clinical
Programs"), a copy of which is attached hereto as EXHIBIT C and made a part
hereof. PROVANTAGE and AMS shall work cooperatively in the implementation of
such additional programs and services to be performed by PROVANTAGE. In
addition, PROVANTAGE agrees to offer to AMS any other relevant services or
programs that it makes available to PROVANTAGE's other clients at terms to be
agreed upon by the parties.
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                       III. PRESCRIPTION DRUG MAIL SERVICE

14.  APPOINTMENT. Except as provided herein, AMS hereby appoints PROVANTAGE as
its exclusive Prescription Drug Mail Service provider for the Plans during the
Initial Term, and PROVANTAGE hereby accepts such appointment.

15.  AUTHORITY. PROVANTAGE hereby agrees to perform all of the following
services with respect to the Plans, and AMS hereby grants PROVANTAGE the
authority and empowers PROVANTAGE to perform such services:

           A.     To provide and dispense all prescribed legend drugs, insulin
                  and insulin syringes, (collectively referred to herein as
                  "Pharmaceuticals"), as set forth in the Plan Parameters,
                  subject to availability. Such Pharmaceuticals shall be
                  supplied in amounts prescribed by a physician, or as indicated
                  in the Plan Parameters. Whenever possible, and subject to
                  state guidelines and the dispensing pharmacist's professional
                  discretion, PROVANTAGE agrees to dispense the generic drug or
                  the lowest cost equivalent item currently available to
                  PROVANTAGE. In addition, at the request of a Plan Participant,
                  PROVANTAGE shall also dispense Pharmaceuticals not covered by
                  the Plan Parameters at the expense of Plan Participants in
                  accordance with EXHIBIT B.

           B.     To label and package the Pharmaceuticals as required by
                  applicable State and Federal Laws and Regulations and as is
                  consistent with industry practices and procedures.

           C.     To provide prepaid delivery of Pharmaceuticals to Plan
                  Participants' residences by U.S. Mail, UPS or an overnight
                  service in accordance with applicable regulations and industry
                  practices and procedures.

           D.     To provide, at PROVANTAGE's expense, toll free telephone lines
                  from 7:00 am - Midnight Central Time, Monday through Friday
                  and 8:00 am - 4:30 pm Central Time, Saturday, computer
                  services, informational brochures and similar administrative
                  services as PROVANTAGE shall determine to be appropriate for
                  the provision of the Prescription Drug Mail Services described
                  herein.

16.  GUARANTEED TIMELINESS OF MAIL SERVICE. PROVANTAGE shall use its reasonable
best efforts to dispense Pharmaceuticals within 48 hours of PROVANTAGE's receipt
of an acceptable prescription. Weekends and holidays are not to be included
within this 48 hour period. If a prescription requires intervention by
PROVANTAGE, PROVANTAGE shall use its reasonable best efforts to dispense
Pharmaceuticals within 120 hours of PROVANTAGE's receipt of such prescription.
AMS acknowledges that PROVANTAGE shall not be responsible for causes and
circumstances beyond the reasonable control of PROVANTAGE and that PROVANTAGE
shall have no liability to AMS or its Plan Participants as a result of any delay
in preparation or delivery of Pharmaceuticals beyond the reasonable control of
PROVANTAGE. PROVANTAGE shall provide AMS with a quarterly report detailing the
timeliness of PROVANTAGE's processing of the Pharmaceuticals. In the event that
the actual turnaround time of performance in any one calendar year is less than
that which was guaranteed by PROVANTAGE hereunder, PROVANTAGE shall pay AMS $300
for each full percentage point required to meet the guaranteed turnaround time
up to a maximum annual penalty of $5,000.

These penalties shall be in addition to any other rights, remedies or recoveries
AMS may have under this Agreement or available at law or in equity.

PROVANTAGE shall have no obligation to provide Pharmaceuticals to any Plan
Participant until PROVANTAGE receives from such Plan Participant any applicable
copayment charges. In the event that PROVANTAGE receives a request from a Plan
Participant to dispense Pharmaceuticals on an expedited basis, PROVANTAGE shall
collect such additional expedited costs from the Plan Participant.
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17.  PRESCRIPTIONS. PROVANTAGE assumes no liability or responsibility for the
accuracy, efficacy or timely receipt of prescriptions, orders or other
directions by physicians to supply Pharmaceuticals to Plan Participants.
PROVANTAGE reserves the right to refuse to fill any prescription that
professional judgment dictates should not be dispensed. Notwithstanding the
foregoing., PROVANTAGE guarantees a 99.99% accuracy rate for dispensing
Pharmaceuticals hereunder and shall reimburse AMS for the drug cost and
dispensing fee of any inaccurately dispensed Pharmaceutical. In the event that
the accuracy ratio falls below that which was guaranteed in any one calendar
year, PROVANTAGE will pay to AMS $300 for each tenth of a percent required to
meet the guaranteed rate up to a maximum annual penalty of $5,000. AMS shall be
permitted to review at PROVANTAGE's premises the quarterly reports generated and
maintained by PROVANTAGE detailing the accuracy of PROVANTAGE's processing of
the Pharmaceuticals.

These penalties shall be in addition to any other rights, remedies or recoveries
AMS may have under this Agreement or available at law or in equity.

18.  BILLING AND REIMBURSEMENT. With respect to each prescription filled by
PROVANTAGE, AMS shall pay PROVANTAGE the charges set forth in the Data Sheet
attached hereto or the applicable Plan Parameters plus any applicable state or
federal sales or use taxes.

19.  REPORTS. PROVANTAGE shall furnish to AMS a monthly report reflecting the
Pharmaceuticals dispensed pursuant to this Agreement, the details of which AMS
agrees to treat as confidential under applicable federal and state guidelines.

                            IV. FORMULARY MANAGEMENT

20.  APPOINTMENT. Except as provided herein, AMS hereby appoints PROVANTAGE as
its exclusive formulary management agent for the Plans during the Initial Term,
and PROVANTAGE hereby accepts such appointment.

21.  AUTHORITY. PROVANTAGE hereby agrees to perform various formulary management
services with respect to the Plans, and AMS hereby grants PROVANTAGE the
authority and empowers PROVANTAGE to perform those formulary management services
as described herein, and as may be agreed to in writing from time to time by AMS
and PROVANTAGE. In addition, PROVANTAGE shall offer to AMS those formulary
management services as described in Paragraph 1 of the Standard Clinical
Programs as set forth on EXHIBIT C. PROVANTAGE and AMS shall work cooperatively
in the implementation of such services to be performed by PROVANTAGE. In
addition, PROVANTAGE agrees to offer to AMS any other relevant formulary
management services or programs that it makes available to PROVANTAGE's other
clients at terms to be agreed upon by the parties.

22.  PROVANTAGE FORMULARY. The PROVANTAGE formulary (the "Formulary") is a
prescription drug formulary containing a listing of preferred medications in the
most commonly prescribed therapeutic categories. The Formulary has been prepared
by licensed clinical pharmacists, and is based upon evaluation of the quality,
efficacy, safety and cost of various pharmaceutical products. The list of drugs
on the Formulary may be modified from time to time as a result of PROVANTAGE's
continuing evaluation of the Formulary, based upon factors including but not
limited to medical appropriateness, manufacturer rebate arrangements and patent
expirations.

PROVANTAGE and AMS agree to implement the Formulary with respect to the Plans
and hereby grants AMS the right to use, during the term of this Agreement,
PROVANTAGE's Formulary. AMS shall distribute copies of the Formulary to all Plan
Participants at the time identification cards are sent out. With AMS' full
cooperation and assistance, PROVANTAGE may implement various Formulary
compliance programs and cost containment initiatives, which may include
communication with Plan Participants, Participating Pharmacies and/or treating
physicians. The parties will work together in good faith to develop innovative
products, including products utilizing restrictive drug formularies and/or
<PAGE>   9
restrictive pharmacy networks. PROVANTAGE agrees to provide to AMS updates to
the Formulary at least quarterly and agrees to cooperate with AMS in AMS'
suggested modifications to such Formulary.

AMS understands and agrees that AMS' right to utilize the Formulary is limited
solely to AMS' own use in connection with the Plans. AMS further understands and
agrees that, except in connection with such limited use, AMS shall at no time
copy, distribute, sell or otherwise provide the Formulary to any third party
without PROVANTAGE's prior written approval. On or prior to termination of this
Agreement, AMS shall cease all use of the Formulary and shall return to
PROVANTAGE all copies in its possession. Plan Participants and any other parties
to whom AMS has provided the Formulary shall be instructed by AMS to discontinue
use of the Formulary and to destroy all copies on or before the effective date
of termination. Upon PROVANTAGE's request, AMS shall provide proof to PROVANTAGE
that it has complied with all of the terms and conditions set forth in this
paragraph.

If PROVANTAGE implements a program that causes a Plan Participant's prescription
to be changed from one chemical entity to another without first gaining the
consent of AMS, PROVANTAGE shall pay AMS a penalty of $1,000. PROVANTAGE shall
also reimburse AMS for any excess amount paid by the Plan Participant for a
higher cost drug. ProVantage understands and agrees to this provision up to a
maximum penalty of $5,000 per year.

This penalty shall be in addition to any other rights, remedies or recoveries
AMS may have under this Agreement or available at law or in equity.

23.  PHARMACEUTICAL MANUFACTURER'S INCENTIVE PAYMENTS. Incentive payments may be
received from certain pharmaceutical manufacturers as a result of the inclusion
of such manufacturers' products on the Formulary ("Incentive Payments").
PROVANTAGE will provide AMS with the amount of Incentive Payments received by
PROVANTAGE on behalf of AMS or the Plans, based upon the utilization of
participating manufacturers' Formulary included drugs to Plan Participants, as
described in Part 6 of the Data Sheet.

AMS agrees that during the term of this Agreement, neither AMS nor the Plans
will directly or indirectly negotiate or arrange or contract in any way with any
entity for Incentive Payments related to the purchase of prescription drugs from
any pharmaceutical manufacturer during the Initial Term of this Agreement. In
the event AMS or any of the Plans negotiate or arrange with a pharmaceutical
manufacturer or any other entity for Incentive Payments related to the purchase
of prescription drugs or services during the Initial Term of this Agreement,
PROVANTAGE may, in addition to any other remedy available at law or in equity,
immediately terminate AMS' and the Plans' participation in the PROVANTAGE
Formulary program, and PROVANTAGE shall be entitled to retain 100% of any and
all Incentive Payments due to AMS under this Agreement which have not been paid
to AMS as of the date AMS' participation so terminates. The parties acknowledge
and agree however that AMS reserves the right to submit requests for proposals
to other prescription benefit managers nine months prior to the end of the
Initial Term of this Agreement, and PROVANTAGE shall not consider such activity
to be a violation of this Section or the Agreement as long as PROVANTAGE remains
the exclusive provider of services hereunder in accordance with the terms of
this Agreement.

                         V. GENERAL TERMS AND CONDITIONS

24.  APPLICABLE PLAN. AMS authorizes PROVANTAGE to fill prescriptions and
reimburse Participating Pharmacies or Plan Participants in accordance with this
Agreement, including the Plan Parameters and the Data Sheet. The Plan Parameters
are expressly incorporated into this Agreement and must be completed prior to
PROVANTAGE providing any services hereunder. The Plans shall be in effect for
the term of this Agreement unless modified by AMS. AMS may elect to amend the
Plans, with sufficient written notice to PROVANTAGE.
<PAGE>   10
25.  TERM OF AGREEMENT. Subject to the terms and conditions of the following
paragraph, the initial term and commencement date of this Agreement shall be
three (3) years commencing January 1, 2000, as indicated on the Data Sheet, and
ending at the close of business on December 31, 2002 (the "Initial Term"). At
the end of the Initial Term, and on each anniversary thereafter, the term of
this Agreement shall automatically renew for successive one (1) year terms,
unless either party notifies the other party of its intent to terminate this
Agreement at the end of the then-current term, which notice shall be given at
least ninety (90) days prior to the expiration of the then-current term.

26.  TERMINATION. This Agreement may be terminated by either party as of the
date written notice of such termination is received by the other party in the
event that:

     A.   any law or regulation becomes effective after the date of this
          Agreement which would render the services provided by PROVANTAGE under
          this Agreement in violation of such law or regulation; or

     B.   any law or regulation becomes effective after the date of this
          Agreement which would render the Plans provided by AMS under this
          Agreement in violation of such law or regulation; or

     C.   the non-terminating party fails to make any of the payments referred
          to in this Agreement or breaches any of the other terms and provisions
          of this Agreement, and such payment is not made (in the absence of a
          bona fide dispute) or such breach is not cured within 30 days after
          the date the terminating party has given written notice to the other
          of such late payment or breach; or

     D.   the non-terminating party shall make an assignment for the benefit of
          creditors, is adjudicated insolvent, has a receiver or trustee
          appointed for a substantial part of its property, or has a proceeding
          commenced against it which will substantially impair its ability to
          perform hereunder.

In addition, AMS shall have the right to terminate this Agreement in the event
that PROVANTAGE does not allow a Regulator (as hereinafter defined) or AMS or
its designated outside auditing firm access to PROVANTAGE and its books and
records for auditing purposes in connection with Paragraphs 9 and 33 of this
Agreement, provided AMS has provided reasonable notice of such audit, agrees to
the reasonable audit procedures in PROVANTAGE'S External Account Audit Policy
and the requested audit procedure would not have a disruptive effect on the
normal service levels provided by PROVANTAGE to its other clients.

AMS is responsible for all of PROVANTAGE's post termination processing charges
in accordance with the terms of this Agreement. Claims that are received and
processed by PROVANTAGE after termination will be subject to the rate so
specified on the Data Sheet for a period of NINETY (90) days after the effective
date of termination of this Agreement. AMS remains responsible for the payment
of all claims submitted to PROVANTAGE with a date of service prior to the
effective date of termination, as well as all of PROVANTAGE's administrative
charges during the NINETY (90) day period after termination.

PROVANTAGE shall have the right to advise Participating Pharmacies that
effective on the termination date, AMS' Plan Participants are not eligible to
receive benefits under the Plan. The post-termination fees indicated on the Data
Sheet will apply. The termination of this Agreement by either party shall not
affect any liabilities of AMS for the payments and charges due PROVANTAGE or its
Participating Pharmacies. These rights shall be in addition to all other rights
and remedies of PROVANTAGE as allowed by law or in equity. In addition, the
termination of this Agreement by either party shall not relieve PROVANTAGE or
its Participating Pharmacies of its/their post termination responsibilities.
These rights shall be in addition to all other rights and remedies of AMS as
allowed by law or in equity.
<PAGE>   11
27.  CHANGE OF CONTROL. In the event that AMS experiences a Change of Control
(as hereinafter defined) and either (i) this Agreement is terminated following
such Change of Control during the Initial Term, except in accordance with
Section 26, or (ii) AMS loses an amount equal to or greater than one-third of
its total Plan Participants as compared to its total Plan Participants as of the
date hereof (a "Substantial Loss of Lives"), the parties acknowledge that
PROVANTAGE will suffer a material adverse impact on its business which may not
be susceptible of precise determination. In such event, AMS shall pay to
PROVANTAGE the sum of $100,000 per month for every full calendar month between
the date of AMS' termination and December 31, 2002. AMS acknowledges and agrees
that the foregoing amounts are a reasonable approximation of the damages
PROVANTAGE will suffer due to a Change of Control that results in an early
termination by AMS or a Substantial Loss of Lives and shall be deemed liquidated
damages and not a penalty. This Section 27 shall apply to any successor or
assignee of AMS permitted under this Agreement.

For purposes of this Paragraph, a "Change of Control" shall be deemed to have
occurred if, after the Commencement Date of the Agreement a majority of
Directors of American Medical Security Group, Inc. ("AMSG") cease to continue to
serve as Directors of AMSG as the direct or indirect result of, or in connection
with the occurrence of: (a) any person, including a "group" as defined in
Section 13(d)(3) of the Securities Exchange Act of 1934, becoming, directly or
indirectly, the beneficial owner of securities of the Company, or any other
subsidiary, representing more than fifty percent (50%) of the combined voting
power of the then outstanding securities of AMSG that may be cast for the
election of Directors of the Company; or (b) a cash tender or exchange offer, a
merger or other business combination, a contested election of directors, or any
combination of these transactions.

28.  RELATIONSHIP BETWEEN PARTIES. Nothing in this Agreement shall be construed
to constitute either party a partner, joint venturer, employee or agent of the
other, nor shall either party have authority to bind the other in any respect,
it being intended that each shall remain an independent contractor solely
responsible for its own actions. No employee or agent of one party hereto shall
be considered an employee or agent of the other party hereto. The Participating
Pharmacies which provide services to the Plan Participants shall also do so as
independent contractors.

29.  LIST OF ELIGIBLE PLAN PARTICIPANTS. The parties acknowledge that PROVANTAGE
has a list of all eligible Plan Participants and the current Plan Parameters.
AMS is responsible for providing PROVANTAGE with any changes to such list or
parameters, (additions, deletions and/or terminations) in writing as soon as
reasonably possible after they occur. Provided AMS has provided PROVANTAGE with
accurate and complete eligibility data, PROVANTAGE shall update its eligibility
records within one business day after receipt from AMS. PROVANTAGE agrees that
its failure to process batch eligibility data within this timeframe due to
errors by PROVANTAGE or failures within PROVANTAGE's system will result in
PROVANTAGE paying to AMS a penalty of 4% of PROVANTAGE's electronic claims
administrative fee for the then current billing period for each incident for
which PROVANTAGE has a failure hereunder, up to a maximum annual penalty of
$5,000. This penalty shall be in addition to any other rights, remedies or
recoveries AMS may have under this Agreement or available at law or in equity.

In the event of a Plan Participant's termination, such Plan Participant(s) and
their dependents will be considered eligible for up to one full business day
after notification has been received by PROVANTAGE. Until such time, AMS will be
responsible for all liabilities incurred by the terminated Plan Participant(s)
and their dependents. AMS shall hold PROVANTAGE harmless and without liability
for any errors or omissions, or any related problems that may result from AMS'
failure to provide an accurate, updated listing of eligible Plan Participants.

30.  COMMUNICATION TO PLAN PARTICIPANTS.PROVANTAGE recognizes the relationship
between AMS and Plan Participants. As such, PROVANTAGE shall not communicate
directly with Plan Participants except in its performance of its services
hereunder. PROVANTAGE shall provide AMS with a draft of all written non-standard
communications to be sent to Plan Participants for AMS' prior review.
<PAGE>   12
31.  NON-LIABILITY. Without limiting any other indemnification set forth
elsewhere in this Agreement, AMS agrees to indemnify, defend, and hold
PROVANTAGE harmless from liability for any claim, injury, demand or judgment
based on contract, tort, or other grounds (including warranty of
merchantability) arising directly or indirectly out of:

     A.   PROVANTAGE's providing Drug Utilization Review (DUR) services
          described herein; and

     B.   Payment of fraudulent claims or filling of fraudulent prescriptions if
          the fraud is committed by AMS, a Plan Participant or any party other
          than PROVANTAGE. "Fraudulent claims" shall include: (i) the
          unauthorized, illegal or wrongful use of any card issued by AMS to any
          of AMS' Plan Participants, and (ii) the wrongful use of any card that
          is lost or stolen until notification is received by PROVANTAGE.

AMS acknowledges that the Participating Pharmacies have been chosen by
PROVANTAGE based on their willingness to provide pharmacy services to the Plan
Participants. In addition, PROVANTAGE has contractually required that the
Participating Pharmacies have met the following minimum required enrollment
criteria:

     U.   State and federal pharmacy licenses;

     V.   Possession of individual practitioner's malpractice insurance;

     W.   Possession of pharmacy's malpractice insurance;

     X.   Federal tax identification number;

     Y.   Proof of individual pharmacist's licensing; and

     Z.   Acceptable disciplinary history.

PROVANTAGE has not performed any other investigation or review of any
Participating Pharmacy's operations.

In addition, and without limiting the generality of the foregoing, each party
agrees to indemnify, defend and hold harmless the other party and its directors,
officers and employees acting in the scope and course of their employment and
not as Plan Participants against all claims, lawsuits, settlements, judgments,
costs, penalties and expenses, including attorney's fees, with respect to this
Agreement and the acts of the indemnifying party or its employees, acting alone
or in collusion with others, if it determined that the indemnified party's
liability therefor was the direct consequence of negligence, criminal conduct or
fraud on the part of the indemnifying party or its directors, officers or
employees.

32.  NOTICES. All notices provided for in this Agreement shall be in writing and
shall be sent by registered or certified mail, express mail, facsimile, or
delivered in person to the other party at the address above or indicated on the
Data Sheet or such other address as may be provided to the other party in the
same manner as that provided for giving of any notice. All notices shall be
deemed to have been received on the third (3rd) day after the date said notice
was mailed; or twenty four (24) hours following the time of said notice if sent
by facsimile, or immediately upon personal delivery.

33.  COOPERATION WITH REGULATORY AUDITS. PROVANTAGE acknowledges that AMS is
involved in the business of insurance, and as such, AMS is subject to certain
laws related to the business of insurance. PROVANTAGE also acknowledges that the
services provided by PROVANTAGE hereunder are related to AMS' providing its
insurance services to Plan Participants. In the event that it is requested by a
state's insurance regulator or its agent or representative (collectively a
"Regulator") that
<PAGE>   13
the Plans or the related services provided by PROVANTAGE be examined, audited or
inspected, PROVANTAGE shall make its books and records and all other aspects of
its operations related to this Agreement available to such Regulator for such
examination, inspection or audit, as required by applicable law.

34.  MAINTENANCE OF RECORDS. PROVANTAGE shall maintain such records with regard
to services provided hereunder as it shall determine to be necessary and
appropriate under the circumstances and as may be required under applicable
laws, rules and regulations. PROVANTAGE shall have no responsibility for the
maintenance of any records by or which are the obligation of AMS. Records kept
by PROVANTAGE with respect to AMS' Plan Participants may be reviewed by AMS
during regular business hours, at AMS' expense provided, however, that no such
review shall relate to records for prescriptions dispensed more than two (2)
years prior to the date such review is requested, except if requested by a
Regulator.

35.  OWNERSHIP OF INFORMATION. AMS shall be the owner of administration and
claims processing information in accordance with applicable state laws,
including insurance regulations and rules. Upon termination of this Agreement,
at AMS' option, such information shall be forwarded to AMS at AMS' sole cost and
expense. PROVANTAGE shall have the right to use all such information for
purposes of this Agreement.

36.  ACCESS TO PROLINK AND PROVQUERY. Subject to a separate license agreement(s)
to be negotiated by the parties, at no fee, PROVANTAGE will grant to AMS a
personal, non-transferable, non-exclusive license to use PROVANTAGE's ProLink
and ProVQuery programs in connection with this Agreement.

37.  CLIENT SERVICE TEAM. PROVANTAGE shall establish an AMS Account Service Team
("AMS Service Team") during the term of this Agreement. Initially the team
should be headed up by Glen Laschober. In addition, PROVANTAGE will have
representatives from its Benefit Design and Analysis, National Accounts,
Information Systems, Marketing, Trade Relations, Clinical and Operations
Departments. The AMS Service Team shall meet with representatives from AMS for a
full day each month during the term of this Agreement to identify cost
reductions, service level improvements and sales and marketing opportunities
that positively impact AMS. Should PROVANTAGE change AMS' primary contact in
Client Relations without AMS' consent as to such contacts replacement, which
consent shall not be unreasonably withheld, PROVANTAGE shall pay AMS a $5,000
penalty. In addition, should PROVANTAGE fail to meet with AMS within two weeks
of any scheduled meeting in accordance with this Paragraph for reasons unrelated
to AMS, PROVANTAGE shall pay AMS a penalty of $500 per occurrence up to a
maximum annual penalty of $5,000. These penalties shall be in addition to any
other rights, remedies or recoveries AMS may have under this Agreement or
available at law or in equity.

38.  CONFIDENTIALITY. Each party to this Agreement agrees that it shall receive
and hold in confidence any knowledge or information (including this Agreement
and all compensation, terms and conditions thereof) concerning the affairs or
business of the other party, and the other party's programs, procedures, or
systems and will not, during or after the term hereof, disclose same to any
third party or use same for the benefit of itself or any other person, firm or
corporation related to or associated with it in any way, except as may be
required for the performance of this Agreement or as may be required by law.
Each party agrees to hold the other party harmless from liability for any claim,
injury, demand or action based on the unauthorized release of any of the
above-described confidential information.

In the performance of its obligations under this Agreement, PROVANTAGE will
receive private and confidential information concerning the Plan Participants.
PROVANTAGE is sensitive to the confidential nature of the files it maintains and
warrants that it shall hold all such information confidential and shall not
disclose such information to any entity other than AMS, unless required by law
or to enable its performance under this Agreement.
<PAGE>   14
39.  NO THIRD PARTY BENEFICIARIES. Except as set forth in Paragraph 3 above, no
individual person, Plan Participant, insurance company, third party payer or
other entity, other than PROVANTAGE and AMS (except governmental authorities to
the extent required by law), is or shall be entitled to bring any action to
enforce any provision of this Agreement against either of the parties hereto,
and that the covenants, undertakings, and agreements set forth in this Agreement
shall be solely for the benefit of, and shall be enforceable only by, the
parties hereto, or their respective successors and assignees as permitted
hereunder.

40.  EXCLUSIVITY. With respect to each Plan, PROVANTAGE shall be the sole and
exclusive provider of the services described in this Agreement to AMS during the
Initial Term of this Agreement. In the event that this Agreement automatically
renews for successive one (1) year terms after the Initial Term, PROVANTAGE
shall no longer be the exclusive provider of any of the services described in
this Agreement. However, nothing in this Agreement shall prohibit PROVANTAGE
from contracting with any other person, firm, corporation or other entity for
any purpose whatsoever for the providing or delivery of the same or similar
services as those described in this Agreement. In limitation of the foregoing,
PROVANTAGE recognizes and agrees to the exclusivity limitation in Section 1 of
this Agreement.

41.  NON-DISCRIMINATION. PROVANTAGE shall not discriminate against any AMS or
Plan Participant on the basis of race, color, sexual orientation, marital
status, disability, national origin, creed, sex or age.

42.  ASSIGNMENT. This Agreement shall not be assignable by either party to any
other person or entity, and any attempted assignment shall be void and of no
force and effect, unless the written consent of the non-assigning party shall
have first been obtained, which consent shall not be unreasonably withheld.
PROVANTAGE acknowledges and agrees that AMS has affiliate corporations
including, but not limited to, AMS, Inc., that perform administrative services
to Holdings, UWLIC, Unity and AMH in connection with this Agreement.

43.  REGULATORY COMPLIANCE. AMS acknowledges that the Plans are or may be
"employee welfare benefit plans" as defined in the Employee Retirement Income
Security Act of 1974, as amended ("ERISA"), 29 U.S.C. ss. 1001 et seq., and the
regulations promulgated under that act. PROVANTAGE will provide AMS with any
information in PROVANTAGE's possession necessary for AMS and the Plans to comply
with any laws or regulations applicable to Plans, but AMS' compliance with any
such laws and regulations shall be the sole responsibility of AMS and/or the
Plans and AMS shall comply and ensure that the Plans comply with all such laws
and regulations. PROVANTAGE will obtain and maintain any licenses or regulatory
approvals necessary for it to perform PROVANTAGE's services under the Agreement.
AMS shall not name PROVANTAGE or represent that PROVANTAGE is, and PROVANTAGE
shall not be, a Plan Administrator or a named fiduciary of the Plan as those
terms are used in ERISA. AMS shall have complete discretionary, binding and
final authority to construe the terms of the Plan, to interpret ambiguous Plans
language, to make factual determinations regarding the payment of claims or
provisions of benefits, to review denied claims and to resolve complaints by
Plan Participants.

44.  PRIOR AGREEMENTS. This Agreement is intended to supplant, replace and
supersede the 1996 Agreement, the 1995 Agreement and that certain Maintenance
Prescription Drug Plan Agreement between AMS and PROVANTAGE dated September 2,
1994 (collectively the "Prior Agreements"). As of the commencement date of this
Agreement, said Prior Agreements shall be null and void, except with respect to
any obligations which arose prior to the commencement date of the term of this
Agreement.

45.  EMPLOYEES. AMS agrees that during the term of this Agreement, and for a
period of one (1) year thereafter, AMS and AMS' affiliates will not, directly or
indirectly, hire or employ, or solicit or offer employment to any employee of
ShopKo Stores, Inc. ("ShopKo") or any of ShopKo's subsidiaries, including
without limitation, PROVANTAGE, without ShopKo's prior written consent. The
foregoing limitation shall apply only with respect to ShopKo employees who,
during the term of their employment
<PAGE>   15
with ShopKo, held a management level position or any position within ShopKo's
MIS/computer systems departments.

PROVANTAGE agrees that during the term of this Agreement, and for a period of
one (1) year thereafter, PROVANTAGE and PROVANTAGE's affiliates including, but
not limited to ShopKo Stores, Inc., will not, directly or indirectly, hire or
employ, or solicit or offer employment to any employee of American Medical
Security Group, Inc., or any of American Medical Security Group, Inc.'s
subsidiaries, including without limitation, AMS, without American Medical
Security Group, Inc.'s prior written consent. The foregoing limitation shall
apply only with respect to AMS employees who, during the term of their
employment with AMS, held a management level position or any position within
AMS' IT/computer systems departments.

46.  NETWORK MAINTENANCE AND ACCESS. PROVANTAGE guarantees that no more that 15%
of the Participating Pharmacies shall voluntarily terminate their agreements
with PROVANTAGE during any one calendar year during the term of this Agreement.
If more than 15% terminate in any one calendar year, PROVANTAGE shall pay AMS up
to $500 per year. In addition, PROVANTAGE will guarantee AMS access to a custom
national network of retail Participating Pharmacies that will process at least
95% of the prescription claims that would have been processed in ProVantage's
standard national network of Participating Pharmacies and further guarantees
that number of Participating Pharmacies in urban, suburban and rural categories
through GeoAccess reporting on an annual basis to ensure the following:

     A.   98% of the Plan Participants living in urban areas shall have at least
          one Participating Pharmacy within two miles of their home; and

     B.   99.3% of the Plan Participants living in suburban areas shall have at
          least one Participating Pharmacy within five miles of their home; and

     C.   97.8% of the Plan Participants living in rural areas shall have at
          least one Participating Pharmacy within 15 miles of their home.

Should any of the above percentages of access for the Plan Participants fall
below the levels outlined above for the access standards specified, PROVANTAGE
shall pay to AMS a $250 penalty for each percentage point by which the guarantee
is not met, up to a maximum annual penalty of $5,000.

These penalties shall be in addition to any other rights, remedies or recoveries
AMS may have under this Agreement or in accordance with applicable law.

47.  INSURANCE. During the term of this Agreement, PROVANTAGE shall maintain in
effect errors and omissions insurance, and such other coverages as AMS may
reasonably request, covering PROVANTAGE and the performance of the services
hereunder, such insurance to be obtained in such amounts and from insurance
companies reasonably acceptable to AMS, and shall provide AMS with certificates
of insurance evidencing such coverage from the companies providing the same.

48.  MOST FAVORED NATION STATUS. During the Initial Term of this Agreement,
PROVANTAGE agrees that its compensation package to AMS for the products and
services covered by this Agreement shall be the most favorable as PROVANTAGE
offers to any other similarly situated customer. PROVANTAGE will warrant to AMS
compliance with this provision each year during the Initial Term of this
Agreement; however, nothing in this provision or this Agreement shall obligate
PROVANTAGE to make available to AMS its agreements with other PROVANTAGE
customers.

49.  FILE FORMATTING. The parties acknowledge that PROVANTAGE provided services
to AMS prior to the effective date of this Agreement utilizing file formats that
are compatible to AMS' current formats. In the event that PROVANTAGE makes any
system changes which causes the existing AMS file formats to not be compatible
with PROVANTAGE's system, AMS shall provide PROVANTAGE with its
<PAGE>   16
cost of making such file formatting change. PROVANTAGE will have the option to
either: a) have AMS make such changes and reimburse AMS for its cost, or b)
accept existing AMS file formatting and translate it at PROVANTAGE'S cost to a
file format which meets PROVANTAGE'S new requirements.

50.  MISCELLANEOUS PROVISIONS. The provisions of this Agreement shall bind and
inure to the benefit of the parties hereto and their heirs, legal
representatives and successors. Failure to exercise any of the rights granted
hereunder for any one default shall not be a waiver of the right to exercise any
of these rights for subsequent default. Neither this Agreement nor any term
hereof may be changed, waived, discharged, or terminated orally, but only by an
instrument in writing signed on behalf of both parties. Time is of the essence
in the performance of each and every obligation herein imposed. This Agreement
and all Exhibits attached hereto when executed by all parties constitutes the
entire understanding between the parties hereto. In the event any provision or
part thereof contained in this Agreement shall be determined by a court of
competent jurisdiction to be invalid or unenforceable, such invalidity or
unenforceability shall not affect the validity or enforceability of any other
provision or part thereof contained herein. The headings in this Agreement are
used solely for the purpose of convenience and shall not be deemed to list the
subject of any provision or be considered in the construction thereof. This
Agreement shall be construed and enforced according to the laws of the State of
Wisconsin, without regard to principles of conflict of law, and ERISA, where
applicable . Both parties understand that it is their respective obligation to
comply with all applicable state, federal and local laws, regulations and
guidelines.
<PAGE>   17


         IN WITNESS WHEREOF, the parties hereto have executed this Agreement to
begin as noted in the Data Sheet.

AMERICAN MEDICAL SECURITY HOLDINGS, INC.


By:  /s/ James C. Modaff                               Date: January 7, 2000
   ---------------------------------------------             ---------------
Title:  Executive Vice President, Chief Actuary
       -----------------------------------------

Attest:  /s/ Julie Van Straton                         Date: January 7, 2000
       -----------------------------------------             ---------------


PROVANTAGE HEALTH SERVICES, INC.


By: /s/ Glen C. Laschober                              Date: January 4, 2000
    --------------------------------------------             ---------------

Title:  Executive Vice President
       -----------------------------------------

Attest:  /s/ Michelle H. Fullerton                     Date: January 4, 2000
       ------------------------------------------            ---------------

(Exhibits to this agreement have been omitted and will be furnished
supplementally to the SEC upon request)