National Press Release

CHICAGO, Jan. 6 /PRNewswire-FirstCall/ -- Aon Corporation (NYSE: AOC) today announced that it has completed the sale of all of the issued and outstanding equity interests of AIS Management, LLC, which is the parent company of Auto Insurance Specialists, LLC, to Mercury General Corporation (NYSE: MCY). Aon received $120 million in cash at the closing on January 2, and may receive potential earn out of up to $34.7 million in additional consideration payable over the two year period following the transaction closing date.

About Aon

Aon Corporation (NYSE: AOC) is the leading global provider of risk management services, insurance and reinsurance brokerage, human capital and management consulting. Through its over 36,000 colleagues worldwide, Aon readily delivers distinctive client value via innovative and effective risk management and workforce productivity solutions. Our industry-leading global resources, technical expertise and industry knowledge are delivered locally through more than 500 offices in more than 120 countries. Aon was named the world's "best broker" by Euromoney magazine's 2008 Insurance Survey. In 2008, Aon ranked highest on the Business Insurance ranking of the world's largest insurance brokers based on commercial retail, wholesale, reinsurance and personal lines brokerage revenues. Aon also was ranked by A.M. Best as the number one global insurance brokerage in 2007 and 2008 based on brokerage revenues, and was voted best insurance intermediary, best reinsurance intermediary, and best employee benefits consulting firm in 2007 and 2008 by the readers of Business Insurance. For more information on Aon, log onto http://www.aon.com/.

Safe Harbor Statement

This press release contains certain statements related to future results, or states our intentions, beliefs and expectations or predictions for the future which are forward-looking statements as that term is defined in the Private Securities Litigation Reform Act of 1995. These forward-looking statements are subject to certain risks and uncertainties that could cause actual results to differ materially from either historical or anticipated results depending on a variety of factors. Potential factors that could impact results include: general economic conditions in different countries in which we do business around the world, changes in global equity and fixed income markets that could affect the return on invested assets, fluctuations in exchange and interest rates that could influence revenue and expense, rating agency actions that could affect our ability to borrow funds, funding of our various pension plans, changes in the competitive environment, our ability to implement restructuring initiatives and other initiatives intended to yield cost savings, changes in commercial property and casualty markets and commercial premium rates that could impact revenues, the outcome of inquiries from regulators and investigations related to compliance with the U.S. Foreign Corrupt Practices Act and non-U.S. anti-corruption laws, the impact of investigations brought by U.S. state attorneys general, U.S. state insurance regulators, U.S. federal prosecutors, U.S. federal regulators, and regulatory authorities in the U.K. and other countries, the impact of class actions and individual lawsuits including client class actions, securities class actions, derivative actions, ERISA class actions, the cost of resolution of other contingent liabilities and loss contingencies, our ability to integrate Benfield successfully and to realize the anticipated benefits of the Benfield acquisition. Further information concerning the Company and its business, including factors that potentially could materially affect the Company's financial results, is contained in the Company's filings with the Securities and Exchange Commission.

     Investor Contact:                       Media Contact:
     Scott Malchow                           David Prosperi
     Vice President,                         Vice President,
     Investor Relations                      Global Public Relations
     312-381-3983                            312-381-2485

SOURCE Aon Corporation