MAMSI REPORTS EARNINGS FOR

FOURTH QUARTER AND FISCAL YEAR ENDING 1998

Membership growth continues. As of January 31, 1999 the total number of covered lives under all managed care plans reached 1,820,900. Of that figure, 745,900 are HMO, indemnity and ASO plan members; and 1,075,000 are PPO members. Product membership breaks down as follows:

* Includes indemnity members.

The company’s provider network numbered 30,600 physicians, specialists and affiliate providers; 2,900 hospitals and outpatient facilities; and 11,400 pharmacies as of December 31, 1998.

In other news, the company announced:

• January rate increases (representing 30 % of total renewals) averaged within the target range of 6 to 8 %.

• Its stock buy back program repurchased a total of 5.044 million shares at a cost of $34.4 million in 1998.

• The Washington Business Journal reported the combined enrollment of M.D. IPA and OCI as the largest of all HMOs operating in the metro area in 1998 for the second year in a row. In addition, Alliance PPO, LLC also repeated its performance as having the metro area’s largest PPO membership in 1998.

For the year ahead, the company has a renewed commitment to increase shareholder value. "In 1999, we will focus on disciplined premium increases, aggressively managing medical costs, and controlling top line growth for earnings improvement," stated Thomas P. Barbera, MAMSI CEO & President. "The future of the company looks very bright."

Mid Atlantic Medical Services, Inc. is one of the largest managed care companies in the mid-Atlantic region, with its health plan subsidiaries covering more than 1.8 million lives in Maryland, Washington DC, Virginia, Pennsylvania, North Carolina, Delaware, and West Virginia. The company’s internet address is www.mamsi.com.

Selected Income Statement Information
IN THOUSANDS EXCEPT SHARE AMOUNTS
(UNAUDITED)

MID ATLANTIC MEDICAL SERVICES, INC.
IN THOUSANDS EXCEPT SHARE AMOUNTS
(UNAUDITED)

MID ATLANTIC MEDICAL SERVICES, INC.
IN 000’S EXCEPT PMPM AND PER SHARE
(UNAUDITED)

Note 1: Safe Harbor Statement under the Private Securities Litigation Reform Act of 1995: All forward-looking information or statements contained in this release are based on management’s current knowledge of factors, all with inherent risks and uncertainties, affecting MAMSI’s business. MAMSI’s actual results may differ materially if these assumptions prove invalid. Significant risk factors, while not all-inclusive, are: the possibility of increasing price competition in the Company’s marketplace; the possibility of state or Federal budget mandates that reduce premium levels; the possibility of increased medical expenses due to increased utilization, inflation or legislative mandates; and the possibility that the Company is not able to expand its Service Area as planned. Investors should review other risks and uncertainties contained in Company documents filed with the Securities and Exchange Commission.

Note 2: MAMSI is a regional holding company for health care organizations that provide comprehensive health insurance products and services including: M.D. IPA, a traditional HMO, and M.D. IPA Preferred, an open-ended version of the HMO; Optimum Choice, Inc., a non-federally qualified HMO; Optimum Choice of the Carolinas, Inc. (OCCI); Optimum Choice, Inc. of Pennsylvania (OCIPA); Alliance PPO, LLC, a preferred provider organization; Mid Atlantic Psychiatric Services, Inc. (MAPSI), a preferred provider organization offering managed psychiatric health care services; MAMSI Life and Health Insurance Company, an indemnity insurance company; HomeCall, Inc. and FirstCall, Inc., home health care companies; and HomeCall Pharmaceutical Services, Inc., a mail order pharmacy and home infusion services company.

Note 3: Mid Atlantic Medical Services, Inc. securities are traded on the New York Stock Exchange (NYSE-MME).