CHICAGO (June 18, 2008) - Aon Corporation (NYSE: AOC), the leading provider of global risk management and consulting services, today announced that Michael Grossi, formerly with Atlas Construction Services, has joined the Hawaii operations of Aon Risk Services, Inc. as executive vice president. Additionally, he will serve the Aon Construction Services Group as managing director.

"Michael Grossi brings to Aon a great deal of knowledge about the construction and real estate development industries in Hawaii," said Chad Karasaki, chairman, CEO and resident managing director of Aon's Hawaii office. "Our clients will benefit from his expertise as we continue to work diligently to protect their businesses and provide innovative coverage and sound advice."

Grossi has more than 20 years of risk management experience, including a strong background in the surety and insurance arenas. Prior to joining Aon, Grossi provided surety and insurance brokering services as well as captive consulting to the largest construction and real estate development accounts domiciled in Hawaii.

Grossi holds a bachelor's degree from Fresno State University.

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About Aon Construction Services Group
Aon Construction Services Group employs over 540 employees dedicated to the construction industry in 25 offices across the country. Backed by broad resources, industry knowledge and technical expertise, Aon professionals understand every major sector of the construction industry and help a wide range of clients develop effective risk management and workforce productivity solutions.

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 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. Aon also was ranked by A.M. Best as the number one global insurance brokerage in 2007 based on brokerage revenues, and voted best insurance intermediary, best reinsurance intermediary, and best employee benefits consulting firm in 2007 by the readers of Business Insurance. For more information on Aon, log onto www.aon.com.