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                                                                    EXHIBIT 10.8

        THIS THIRD AMENDMENT TO LEASE (this "Amendment") is made as of this 1st
day of December 1999, by and between HILL MANAGEMENT SERVICES, INC., a Maryland
corporation, agent for the owner ("LANDLORD") and ADVANCE PARADIGM CLINICAL
SERVICES, INC., a Maryland corporation ("TENANT").

                                    Recitals

        A. WHEREAS, Landlord and Paradigm Pharmacy Management entered into a
Lease dated March 16, 1994, as amended by an Amendment to Lease dated October
19, 1996, and a Second Amendment to Lease dated September 30, 1999,
(collectively, the "Lease") for Suites 1000, 600, 601 and 603 consisting of
approximately 30,733 square feet (the "Initial Leased Premises"), which has an
address of 11350 McCormick Rd., Hunt Valley, Maryland 21031, and is known as
Executive Plaza II (the "PROPERTY"). The parties hereby acknowledge and agree
that Tenant commenced occupancy of payment of rent for Suite 603 as of
January 1, 1999, and that the Expiration Date pursuant to Section 1.1. Term of
the second Amendment to Lease Shall be February 28, 2001.

        B. WHEREAS, Landlord and Tenant now desire to amend certain provisions
of the Lease to provide Tenant with additional office space in the Property and
to extend the Lease Term.

                                   Agreements

        NOW, THEREFORE, in consideration of the mutual covenants contained
herein, and other good and valuable consideration, the receipt and sufficiency
of which are hereby acknowledged, Landlord and Tenant agree as follows.

        Section 1. Amendment of Lease. The provisions of the Lease are amended
as follows:

                Term. Commencing November 15, 1999, the term of the Lease shall
be extended for five (5) years such that the Expiration Date of the Lease shall
be February 28, 2001. The renewal option(s) as set forth in Section 1.8 of the
Lease remain in full force and effect and shall apply to the extended lease
term.

        1.2. Leased Premises. Commencing November 15, 1999, the Leased Premises
shall consists of approximately 31,363 square feet, and shall be comprised of
the Initial Leased Premises (Suites 1000, 600, 601 and 603) and an additional
10,630 square feet known as Suite 900 of Executive Plaza II (the "ADDITIONAL
LEASED PREMISES"). The Additional Leased Premises are more particularly
depicted as outlined in red on Exhibit A attached hereto and made a part hereof.

        1.3. Rent. Commencing November 15, 1999, Tenant shall pay to Landlord
annual basic rent of Five Hundred Seventy-Two Thousand Three Hundred
Seventy-Four and 75/100 Dollars ($572,374.75) payable in equal monthly
installments of Forty-Seven Thousand Six Hundred Ninety-Seven and 90/100 Dollars
($47,697.90). Commencing November 15, 2000 and each twelve (12) month period
thereafter, the annual basic rent shall be increased to an amount equal to
percent of the basic rent for the immediately preceding twelve (12) month period
as set forth in Section 2.C of the Lease.

    1.4. Tenant Improvements. Landlord, at its sole cost and expense, shall
construct the Additional Leased Premises using Tenant's choice of building
standard materials in accordance with the revised plan dated July 15, 1999 and
specifications dated February 8, 1999 prepared by Rubelling & Associates
attached hereto and made a part hereof as Exhibit ?? and Exhibit 8.1.

    1.5. Underground Parking. So long as Tenant is not in default under the
Lease, Landlord shall allocate to Tenant 21 additional reserved parking spaces
in the lower level indoor parking area of Executive Plaza. Said spaces shall be
charged at the rate of $80.00 per space per month. Except as otherwise expressly
set forth in this Section 1.5., the terms and conditions of Tenant's use of said
parking spaces shall be governed by a separate Application and Lease for
Executive Plaza II Lower Level Indoor Parking executed by Tenant and
Landlord.

    1.6. Option to Terminate. Tenant shall have the right to terminate their
occupancy of a portion of or all of the sixth ??? February 28, 2001 (the
"TERMINATION DATE"), provided Tenant has notified Landlord in writing of
Tenant's election ??? at lease one hundred twenty (120) days prior to the
Termination Date pursuant to this Section 1.6. From and ???? elected Termination
Date, the Lease as it relates to such space shall be of no further force and
effect and Landlord ??? shall have no further obligations to the other under the
Lease as it relates to such space. Notwithstanding the foregoing, Tenant shall
be responsible to pay and Additional Rent accrued through the respective
Termination Date whether or not it is billed at that time.

        1.7. Right of First Refusal. In any instance where a right of first
refusal has not been granted to another tenant in the Property, Tenant will
have the one-time right of first refusal on any space that becomes available on
the 6th, 7th or 8th floors of the Property.

        Section 2. Titles of Sections. The section titles used in this
Amendment are for convenience of reference only, and do not constitute a part
of this Amendment nor shall they affect the meaning, construction or effect of
this Amendment or ?? Lease.

        Section 3. Definitions. Unless otherwise set forth in this Amendment,
all capitalized terms shall have the same ?????????????

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     Section 5. Representations. Tenant hereby represents and warrants to
Landlord that, as of the date hereof, it (i) is the sole legal and beneficial
owner of all the right, title and interest granted to it by the provisions of
the Lease, (ii) has not sold, transferred or encumbered any or all of such
right, title or interest, and (iii) has the full and sufficient right at law
and in equity to execute and deliver this Amendment as the owner of such right,
title, and interest, without the necessity of having any other person's consent
thereto or joinder therein.

     Section 6. Successors and Assigns. This Amendment and the terms, covenants
and conditions herein contained shall inure to the benefit of and be binding
upon Landlord and its successors and assigns, and Tenant and its permitted
successors and assigns.

     IN WITNESS WHEREOF, Landlord and Tenant have caused this Amendment to be
duly executed under seal on their behalf by their duly authorized
representative, as of the date first above written.


WITNESS/ATTEST                          Landlord:

                                        HILL MANAGEMENT SERVICES, INC.
                                        agents for the owner

/s/ [Signature Illegible]               By: /s/ [Signature Illegible]     (SEAL)
----------------------------------          ------------------------------

                                        Title: VP
                                               ---------------------------------

                                        Date: 12/1/99
                                              ----------------------------------


WITNESS/ATTEST                          Tenant:

                                        ADVANCE PARADIGM CLINICAL SERVICES, INC.

/s/ SUSAN JENKINS                       By: /s/ JOE FILIPEK               (SEAL)
----------------------------------          ------------------------------

                                        Printed Name: Joe Filipek

                                        Title: President & CEO
                                               ---------------------------------

                                        Date:
                                              ----------------------------------



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9TH FLOOR:

     -    Provide all construction in accordance with the floor plan dated
          February 3, 1999 (Drawing E) prepared by Rubelling & Associates.

     -    Renovate lobby floor and walls using building standard wall
          covering, paint, and carpet finishes.

     -    Paint elevator doors.

     -    Replace/remove existing water fountain.

     -    Renovate Ladies and Men's room to include new paint and wall covering
          throughout, new flooring and countertops and wall tile.

     -    Repair or replace (as needed) building standard vertical blinds.

     -    Install uniform, building standard ceiling throughout the leased
          premises.

     -    Install building standard wall covering and a reasonable number of
          incandescent lights in the small and main conference rooms.

     -    Install building standard wall coverings, carpet and additional
          lighting in common stairwell between the 8th and 10th floors.

     -    Install insulation/sound conditioning in the small and large
          conference rooms.

10TH FLOOR:

     -    Recarpet the entire Leased Premises at Paradigm's request anytime
          during the first three (3) years of the five (5) year lease extension.

     -    Paint offices and common areas.

     -    Clean mini blinds.

     -    Shampoo existing carpet (if not replaced)

     -    Replace and clean areas around air vents.

     -    Correct signage on main floor marquee.

     -    Clean Ladies Room and Men's Room to include repainting stall doors.

     -    Repair damaged marble in lobby area (approximately 8 tiles)

     -    Provide 10th floor lounge renovations set forth on Exhibit B-1 (page
          2)

     -    Construct doorway with double doors between the existing reception
          area and conference room.


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                                  [FLOOR PLAN]











                                                                       EXHIBIT A