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                                                                    EXHIBIT 99.1


         AMERICAN MANAGEMENT SYSTEMS, INC. TO APPEAL MISSISSIPPI VERDICT


JACKSON, MISS., August 23, 2000 - American Management Systems, Inc. (AMS) said
it will appeal today's jury verdict against AMS in the case of the State of
Mississippi v. American Management Systems, Inc. in Hinds County Circuit Court.
The jury awarded the State actual and punitive damages totaling $474.5 million.


"We are disappointed, of course, but we are confident the verdict will be
overturned on appeal, "said Paul Brands, AMS Chairman and Chief Executive
Officer.  "The evidence presented in trial clearly demonstrated that AMS worked
hard to resolve issues that arose during the acceptance testing and was on
schedule to have the system in production when the Tax Commission prematurely
terminated the contract."


"It is  unfortunate  that we could not put this situation to rest," said Brands.
"We find the amounts involved inexplicable given that the contract was valued at
$11.2 million, of which approximately $6 million had been paid to AMS."


AMS is an international  business and information  technology  consulting firm -
one of the 20 largest such firms worldwide.  AMS is the premier provider of next
generation  enterprise  business  and  technology  solutions  that  dramatically
improve  business  performance  and create  value for  clients.  AMS's  suite of
eBusiness   strategy,   management,   and  technology   services  make  business
reinvention possible in Internet time for large organizations.  Founded in 1970,
AMS is  headquartered  in Fairfax,  Virginia,  with over 9,000  employees and 59
offices worldwide.  AMS had 1999 revenues of $1.24 billion, with an expansion of
eBusiness  related revenues to $500 million,  an increase of more than 150% over
1998. Forbes magazine ranked AMS among the  best-performing big companies in the
U.S. in their "Best of the Biggest," and FORTUNE magazine placed AMS on its list
of the "100 Best Companies to Work for in America" in 1999. AMS is traded in the
NASDAQ over-the-counter market under the symbol AMSY.


AMS can be found on the World Wide Web at www.ams.com.


Contacts:


Jeff Trexel
(703) 267-5053


Tom Donnelly
(202) 835-8835
(202) 841-5548 cell