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FOR IMMEDIATE RELEASE


         Magellan Investor Contact:                   Aetna Investor Contact:
         Kevin Helmintoller                           Catherine H. Smith
         (404) 814-5742                               (860)273-6184

         Magellan Media Contact:                      Aetna Media Contact:
         Robert Mead                                  Jill B. Griffiths
         (212) 445-8208                               (215)775-6890

                     AETNA U.S. HEALTHCARE COMPLETES SALE OF
                     HUMAN AFFAIRS INTERNATIONAL TO MAGELLAN

               Long-Term Strategic Provider Relationship Commences

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ATLANTA, GA and HARTFORD, CT, December 5, 1997 -- Magellan Health Services, Inc.
(NYSE:MGL)  and Aetna Inc.  (NYSE:AET)  announced  today the  completion  of the
transaction in which Magellan  acquired Human Affairs  International  (HAI), the
behavioral health subsidiary of Aetna U.S. Healthcare.  Terms of the transaction
included  a  payment  of $122.1  million  in cash by  Magellan  at  closing.  In
addition, under the terms of the strategic relationship,  payments of up to $300
million  may be made by  Magellan  over  the  term  of the  long-term  strategic
relationship.  HAI has  become a  wholly-owned  subsidiary  of  Magellan  Health
Services.
         The  two  companies  have  commenced  a  long-term  strategic  provider
relationship  which will provide Aetna U.S.  Healthcare  members with  continued
access to HAI's broad network of behavioral health professionals,  as well as to
Magellan's existing network of behavioral health providers across the country.
         Mac Crawford,  chairman,  president and CEO of Magellan  said,  "We are
pleased to welcome Human Affairs  International as one of our growing behavioral
managed care operations.  The inclusion of the long-term strategic  relationship
with Aetna U.S. Healthcare is

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exciting and should provide HAI with significant growth opportunities over the
term of the agreement while continuing to benefit Aetna U.S. Healthcare."
         "We're pleased to develop a long-term relationship with Magellan, which
not only  maintains HAI behavioral  health  professionals  for our members,  but
allows even greater access to Magellan's  professionals  and  facilities,"  said
Daniel S. Messina, vice president and head of business strategies for Aetna U.S.
Healthcare.
         HAI,  headquartered  in Salt  Lake  City,  provides  behavioral  health
programs to more than 15 million  covered lives, of which the majority are Aetna
U.S. Healthcare members.
         Magellan  Health  Services,  Inc.  is  one  of  the  country's  largest
specialty care managers. Its business units include: Majority owned Green Spring
Health  Services,  a leader in  behavioral  managed care services with nearly 20
million covered lives;  Human Affairs  International  (HAI),  one of the largest
providers of workplace assistance programs in the United States; MENTOR/Magellan
Public  Solutions,  serving public sector  agencies with  privatized  behavioral
health services;  Charter Advantage,  an international  franchisor of behavioral
health care systems;  and 50% interest in Charter Behavioral Health Systems, the
largest operator of free-standing  behavioral facilities in the U.S; and subject
to consummation of a previously announced purchase transaction, Merit Behavioral
Care  Corporation  (MBC),  one of the  largest  providers  of mental  health and
substance  abuse  services  and  employee  assistance  programs  to more than 21
million enrollees and 800 clients.
         Aetna U.S.  Healthcare,  the health business unit of Aetna Inc., is the
nation's leading health benefits  organization with a total health enrollment of
approximately 14 million members nationwide.
         Certain of the  statements  in this press  release  including,  without
limitation,  statements by Magellan  concerning HAI's growth  opportunities  and
amounts  potentially  payable  under  the  strategic   relationship   constitute
forward-looking statements under the Private Securities Litigation Reform Act of
1995. Risk factors such as the ability to  successfully  close and integrate the
MBC transaction and to successfully  integrate the HAI acquisition could prevent
Magellan from  achieving the growth  mentioned.  Also,  the amounts  potentially
payable under the

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strategic relationship are contingent upon a number of factors and no assurances
can be made  that  the  payments  will be made  or  received  by the  respective
parties. For a more complete discussion of these and other risk factors,  please
see Magellan's  Quarterly Report on Form 10-Q for the third fiscal quarter ended
June 30, 1997 filed with the  Securities  and Exchange  Commission on August 14,
1997 and Exhibit 99  contained  in  Magellan's  Annual  Report on Form 10-K,  as
amended for the fiscal year ended  September 30, 1996 filed with the  Securities
and Exchange Commission.