Exhibit (a)(1)(K)



Media Contact:    John Bloomfield  (201) 269-6400
Investor Contact: Laura Jordan  (908) 423-5185



                  MERCK-MEDCO COMPLETES SUCCESSFUL TENDER
                 OFFER FOR PROVANTAGE HEALTH SERVICES, INC.


     FRANKLIN LAKES, N.J., June 15, 2000 - Merck-Medco Managed Care,
L.L.C., the pharmaceutical benefit management services subsidiary of Merck
& Co., Inc. (NYSE: MRK), said today that it has, through a wholly owned
subsidiary, completed a successful tender offer for all of the outstanding
shares of common stock of ProVantage Health Services, Inc. (NYSE: PHS).

     The tender offer expired at 12:00 midnight Eastern Daylight Time
on Wednesday, June 14, 2000. Approximately 17.7 million shares of
ProVantage have been tendered (including 59,100 shares tendered by notice
of guaranteed delivery), representing more than 97 percent of the
company's outstanding shares. Merck-Medco will accept for payment all of
the shares validly tendered at the tender offer price of $12.25 per share.

     Merck-Medco intends to promptly complete the transaction in accordance
with Delaware's short-form merger provisions. As a result of the merger,
each remaining outstanding share of ProVantage will be converted, subject
to appraisal rights, into the right to receive $12.25, in cash, without
interest.

     ProVantage, headquartered in Waukesha, Wisconsin, is a health-care
benefits management and health information company with health benefit
management and health information technology divisions.

     Merck-Medco is the nation's leading provider of high-quality,
affordable prescription-drug care, serving benefit plans of employers,
unions, commercial and government health plans that provide benefits to
more than 53 million Americans, including 14 million older Americans.
Additional information about Merck-Medco is available at
www.merckmedco.com.

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This release contains forward-looking  statements as defined in Section 21E
of the Securities Exchange Act of 1934,  including  statements about future
business  operations,  financial  performance and market  conditions.  Such
forward-looking  statements  involve  risks and  uncertainties  inherent in
business forecasts.
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