Exhibit 99.1

                                                    CONTACTS
                                                    Dennis Milewski, HSB
                                                    (860) 722-5567

                                                    Joe Norton, AIG
                                                    (212) 770-3144

FOR IMMEDIATE RELEASE

                       AIG TO ACQUIRE HSB GROUP, INC. FOR
                COMMON STOCK VALUED AT APPROXIMATELY $1.2 BILLION

NEW YORK and HARTFORD,  August 18, 2000 -- American  International  Group,  Inc.
(NYSE:  AIG) and HSB  Group,  Inc.  (NYSE:  HSB) have  announced  that they have
entered into a definitive  agreement whereby AIG will acquire 100 percent of the
outstanding  stock of HSB Group,  Inc. HSB stockholders  will receive AIG common
stock (or in certain  circumstances  at the option of AIG,  AIG common stock and
cash) with a value equal to $41.00 for each share of HSB common stock. The total
value for the transaction is approximately $1.2 billion.

The  transaction has been approved by the Boards of Directors of both companies,
and is subject to various regulatory  approvals,  as well as the approval of HSB
stockholders.  The  parties  expect that the  transaction  will be able to close
later this year or early next year. In connection  with the  agreement,  HSB has
issued to AIG an option to purchase up to 19.9 percent of its common stock under
certain conditions.

The  transaction  will be treated as a purchase for accounting  purposes.  It is
anticipated that the transaction will qualify as a tax-free  reorganization  for
federal income tax purposes.

Commenting on the  agreement,  AIG Chairman M. R.  Greenberg  said, "We are very
pleased to have reached this agreement to acquire HSB Group, a fine organization
that, through its subsidiary, The Hartford Steam Boiler Inspection and Insurance
Company,  provides specialty insurance coverages that complement AIG's insurance
products.  Hartford Steam Boiler is the largest  insurance company in the United
States  providing  these specialty  property  coverages and has, over the years,
produced  excellent  underwriting  results with an  outstanding  reputation  for
product and service quality. Hartford Steam Boiler will operate as a stand-alone
company with its management team remaining in place.

"As part of AIG,  Hartford  Steam Boiler will be able to take advantage of AIG's
relationships and global network to build its business of specialized  insurance
and inspection  services.  Overseas,  AIG should be able to open significant new
opportunities  for Hartford  Steam  Boiler.  It is  anticipated  that it will be
slightly  accretive to the  earnings of AIG in 2001.  We look forward to working
with HSB's management team in the future," said Mr. Greenberg.

"Our affiliation with AIG provides  significant  opportunities  for HSB's people
and businesses.  This transaction permits HSB to leverage the enormous financial
strength,  market  position  and  international  reach of AIG," said  Richard H.
Booth, HSB Chairman, President and Chief Executive Officer.

AIG is the leading  U.S.-based  international  insurance and financial  services
organization and the largest underwriter of commercial and industrial  insurance
in the United States.  Its member companies write a wide range of commercial and
personal  insurance  products  through a variety  of  distribution  channels  in
approximately 130 countries and jurisdictions throughout the world. AIG's global
businesses  also  include  financial  services and asset  management,  including
aircraft  leasing,  financial  products,  trading  and market  making,  consumer
finance, institutional, retail and direct investment fund asset management, real
estate  investment  management,   and  retirement  savings  products.   American
International  Group,  Inc.'s  common  stock is  listed  on the New  York  Stock
Exchange,  as well as the stock  exchanges  in London,  Paris,  Switzerland  and
Tokyo.

HSB Group,  Inc., the parent company of The Hartford Steam Boiler Inspection and
Insurance  Company,  is a  global  provider  of  specialty  insurance  products,
engineering  services,  and  management  consulting.  The Hartford  Steam Boiler
Inspection and Insurance  Company was founded in 1866 to provide loss prevention
service and  insurance to  businesses,  industries  and  institutions.  For more
information about HSB, visit its web site at www.hsb.com.


Caution concerning forward-looking statements

This press release contains  forward-looking  statements.  These forward-looking
statements  are found in  various  places  throughout  this  press  release  and
include,  without limitation,  statements  concerning the financial  conditions,
results  of  operations  and  businesses  of  AIG  and  HSB  and,  assuming  the
consummation of the acquisition,  the  consolidation of HSB into AIG, as well as
the expected timing and benefits of the acquisition. While these forward-looking
statements  represent  our  judgments  and future  expectations  concerning  the
development  of our business and the timing and benefits of the  acquisition,  a
number of risks,  uncertainties  and other important  factors could cause actual
developments  and  results to differ  materially  from our  expectations.  These
factors  include,  but are not  limited  to,  those  listed in AIG's 1999 Annual
Report on Form 10-K and HSB's 1999  Annual  Report on Form 10-K,  as well as the
failure of the HSB  stockholders to approve the  transaction;  the risk that the
HSB business will not be successfully  integrated into AIG; the costs related to
the  transaction;  the  inability  to  obtain  or meet  conditions  imposed  for
governmental approvals for the transaction;  the risk that anticipated synergies
will not be obtained or not obtained within the time anticipated;  and other key
factors  that we have  indicated  could  adversely  affect  our  businesses  and
financial  performance  contained  in our past and future  filings and  reports,
including those with the United States  Securities and Exchange  Commission (the
"SEC").

More  detailed  information  about those factors is set forth in filings made by
AIG and HSB with the SEC.  Neither AIG nor HSB is under any  obligation  to (and
expressly disclaims any such obligations to) update or alter its forward-looking
statements whether as a result of new information, future events or otherwise.

Further information about proxy materials

AIG and HSB  will be  filing a proxy  statement/prospectus  and  other  relevant
documents concerning the acquisition with the SEC. WE URGE INVESTORS TO READ THE
PROXY STATEMENT/PROSPECTUS AND ANY OTHER RELEVANT DOCUMENTS TO BE FILED WITH THE
SEC,  BECAUSE  THEY CONTAIN  IMPORTANT  INFORMATION.  Investors  will be able to
obtain  the  documents  free of  charge at the SEC's  website,  www.sec.gov.  In
addition,  documents  filed with the SEC by AIG will be available free of charge
from AIG,  70 Pine  Street,  New York,  New York 10270,  Attention:  Director of
Investor  Relations.  Documents filed with the SEC by HSB will be available free
of charge from HSB,  One State  Street,  P.O.  Box 5024,  Hartford,  Connecticut
06102, Attention: James C. Rowan, Jr.

HSB and its directors and executive officers may be deemed to be participants in
the  solicitation  of proxies from the  security  holders of HSB in favor of the
acquisition.  The directors and executive officers of HSB include the following:
R.H. Booth,  S.L. Basch, M.L. Downs,  J.J. Kelley,  W.A. Kerr, N. Mercier,  R.K.
Price, W. Stockdale,  R.C. Walker,  W.B. Ellis,  E.J.  Ferland,  H.H. Fore, C.G.
Campbell, S.W. Leathes, J.B. Alvord, R.G. Dooley and L.D. Rice. Collectively, as
of March 10, 2000, the directors and executive  officers of HSB may be deemed to
beneficially  own  approximately  5.5 percent of the  outstanding  shares of HSB
common  stock.  Security  holders  of  HSB  may  obtain  additional  information
regarding   the   interests   of  such   participants   by  reading   the  proxy
statement/prospectus when it becomes available.