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                                                                   EXHIBIT 10.19

                                                                  EXECUTION COPY

                                                                    May 27, 1999

Mr. Alan B. Masarek
79 Cavalry Road
Weston, Connecticut  06883

Dear Alan:

     The following are the terms and conditions we have agreed to in connection
with your resignation from Advanced Health Corporation d/b/a AHT Corporation
(the "Company") and your severance package. These provisions supercede any
existing employment contracts between the Company and you.

1.   Your resignation as President and Chief Operating Officer of the Company is
     effective as of March 31, 1999.

2.   Severance: You will receive a one-year continuation of salary at your
     current annual salary rate of $250,000 ("Severance Payments"), plus
     benefits as described in Paragraph 5 below, as severance, from April 1,
     1999 to March 31, 2000 (the "Severance Period"). Such Severance Payments
     will be paid on the normal payment intervals provided employees of the
     Company. You will be paid an additional one year continuation of salary at
     your current annual salary rate of $250,000 (the "Additional $250,000
     Payment") in exchange for consulting for up to 24 business days in a form
     and manner reasonably requested by the Company's Board of Directors. Such
     consulting services will be provided during the period from April 1, 2000
     to March 31, 2001 (the "Consulting Period"). The Company will pay you this
     Additional $250,000 Payment less applicable withholdings in one lump sum
     upon execution of this agreement.

3.   You agree to repay your current outstanding loans, principal ($467,475) and
     interest (at the rate of 6% per annum), beginning May 1, 2000 at the rate
     of $15,000 per month with the balance due of all outstanding loans,
     including principal and interest on May 1, 2001.

4.   You will be entitled to receive your current health benefits during the
     Severance Period, (which may be adjusted depending upon a change in health
     carrier, but in no event diminishing the benefits you would have received
     had you still been employed by the Company); life insurance, including
     continued payment by the Company of the premiums related to your $250,000
     whole-life policy and the supplemental disability policy with Massachusetts
     Casualty Company; a $600 per month car allowance; reasonable cellular phone
     and pager use; membership dues with the Young President's Organization not
     to exceed $5,000; and inclusion in the Company's 401-k plan. If at the end
     of such Severance Period, you are not employed, then an extension of such
     benefits will be considered by the Board of Directors.

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5.   You have been vested in 150,136 options to acquire Company stock that will
     remain fully exercisable for up to five years from the commencement of the
     Severance Period.

6.   Your resignation from the Board of Directors of the Company is effective
     March 31, 1999.

7.   You are entitled to receive a success bonus for the sale of the Management
     Services Division of the Company that occurred on May 14, 1999 ("the
     Sale"), equal to $40,000 plus 2.5% of the net proceeds of the Sale.
     Contingent consideration from the Sale received after June 30, 1999 will be
     considered part of the proceeds of the Sale. Any such payments shall be
     made to you within 14 days of receipt by the Company of the proceeds
     related to the Sale.

8.   The terms of your current employment contract related to confidentiality,
     inventions and non-competition shall remain in full force and effect. It is
     expressly understood that the period of any non-competition commences on
     March 31, 1999.

9.   Current arrangements concerning indemnification, including but not limited
     to payment of expenses of officers, directors and employees in connection
     with litigation involving the Company shall remain in full force and effect
     following termination.

10.  This Agreement contains the entire agreement between the parties with
     respect to the subject matter contained herein and supersedes all prior
     agreements or understandings among the parties with respect thereto, other
     than your employment contract and the Company's Senior Executive Loan
     Policy. This Agreement may be amended only by an agreement in writing
     signed by the parties hereto. This Agreement may be executed in
     counterparts, each of which shall be deemed an original document but
     together shall constitute but one agreement.

11.  Any provision of this Agreement that is prohibited or unenforceable in any
     jurisdiction shall, as to such jurisdiction, be ineffective to the extent
     of such prohibition or unenforceability without invalidating the remaining
     provisions hereof, and any such prohibition or unenforceability in any
     jurisdiction shall not invalidate or render unenforceable such provision in
     any other jurisdiction.

     Please confirm your agreement with the foregoing by countersigning this
letter agreement in the space provided below.

                                                 Very truly yours,

                                                 /s/ Jonathan T. Edelson, MD
                                                 ---------------------------
                                                 Jonathan T. Edelson, MD
                                                 Chairman and CEO
AGREED TO AND ACCEPTED:


/s/ Alan B. Masarek
-------------------
Alan B. Masarek

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