Exhibit 99.1

Willis Group Increases Stock Buyback Authorization

    NEW YORK--(BUSINESS WIRE)--Sept. 8, 2004--Willis Group Holdings
Limited (NYSE: WSH), the global insurance broker, today announced that
the Board of Directors approved an increase in the Company's existing
common share buyback authorization from $300 million to $500 million.
    The buyback is an open-ended plan to purchase, from time to time
in the open market or through negotiated trades with persons who are
not affiliates of the Company, shares of the Company's common stock.
    To date in 2004, the Company has repurchased approximately $250
million of its common stock.
    Willis Group Holdings Limited is a leading global insurance
broker, developing and delivering professional insurance, reinsurance,
risk management, financial and human resource consulting and actuarial
services to corporations, public entities and institutions around the
world. With over 300 offices in some 80 countries, its global team of
14,500 Associates serves clients in some 180 countries. Additional
information on Willis may be found on its web site www.willis.com.

    CONTACT: Willis Group Holdings Limited
             Investors:
             Kerry K. Calaiaro, 212-837-0880
             calaiaroke@willis.com
                    or
             Media:
             Nicholas Jones, +44-20-7488-8190
             jonesnr@willis.com
                    or
             Dan Prince, 212-837-0806
             princeda@willis.com