Aon Corp. (NYSE: AOC) announced Roy C. Keller has joined the company as senior vice president of global real estate. He is based in Chicago.

In this role, Keller is responsible for managing Aon's real estate portfolio around the world, ensuring optimal use of facilities and driving cost efficiency in the acquisition and disposition of properties.

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"Providing distinctive value to our clients -- and giving our colleagues the tools they need to do so -- are our highest priorities," said Greg Case, president and chief executive officer of Aon Corp. "Roy's capabilities are invaluable as we ensure that our properties and facilities offer environments in which our colleagues can thrive and from which we can best serve our clients."

Keller reports to Andrew Appel, the chairman and chief executive officer of Aon Consulting Worldwide and the executive responsible for information technology, real estate and purchasing for Aon worldwide.

"Aon will be well served with Roy on the team, both for his experience in delivering bottom-line results, and for his experience in establishing a platform from which we will build workplaces that foster greater communication and efficiency among our team," said Appel.

Before joining Aon, Keller was deputy director of real estate at JP Morgan Chase, where he was responsible for directing a portfolio of 70 million rentable square feet with an annual expense base of $2.5 billion. His strategic efforts reduced the portfolio by millions of square feet all while meeting the business needs which added directly to the bottom line. Previously he was vice president of corporate real estate for Citigroup. Keller is a mathematics major from Lehigh University in Bethlehem, Pa.

About Aon

Aon Corporation (http://www.aon.com/) is a leading provider of risk management services, insurance and reinsurance brokerage, human capital and management consulting, and specialty insurance underwriting. There are 43,000 employees working in Aon's 500 offices in more than 120 countries. Backed by broad resources, industry knowledge and technical expertise, Aon professionals help a wide range of clients develop effective risk management and workforce productivity solutions.

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, our ability to execute the stock repurchase program, our ability to obtain regulatory or legislative changes to permit continuous sales of our supplemental Medicare health product, changes in commercial property and casualty markets and commercial premium rates that could impact revenues, changes in revenues and earnings due to the elimination of contingent commissions, other uncertainties surrounding a new compensation model, the impact of investigations brought by state attorneys general, state insurance regulators, federal prosecutors, and federal regulators, the impact of class actions and individual lawsuits including client class actions, securities class actions, derivative actions, ERISA class actions, the impact of the analysis of practices relating to stock options, the cost of resolution of other contingent liabilities and loss contingencies, and the difference in ultimate paid claims in our underwriting companies from actuarial estimates. 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.

  Media Contacts:
  Chicago
  Al Orendorff
  1.312.381.3153
  Al_Orendorff@aon.com

First Call Analyst:
FCMN Contact: Al_Orendorff@asc.aon.com

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SOURCE: Aon Corporation

CONTACT: Al Orendorff of Aon Corporation, +1-312-381-3153,
Al_Orendorff@aon.com

Web site: http://www.aon.com/