LONDON, 17 April 2008 – Aon has appointed Gerry Callaghan as sales and marketing director in its specialist private clients, affinity and SME business.

In this newly created role for Aon's Personal & Group Programmes (PGP) unit, Gerry will be responsible for developing new niche lines and leading the business development and marketing teams. This will ensure that Aon continues to lead the field in terms of client proposition and, in turn, retain clients and drive new business.

Gerry previously worked as sales and marketing director of absence management company AHP and as managing director of Royal & SunAlliance's 'You at Work' benefits programme.

Joanna Caparn, CEO of PGP, commented: "Gerry's role is critical in building upon our market leading position . We will benefit from his ability to think strategically and act tactically, while sharing best practice in client interaction by understanding and meeting their requirements."

Ends

For more information contact:

Reuben Aitchison

020 7086 7201

reuben.aitchison@aon.co.uk

http://aon.mediaroom.com

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 37,000 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 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

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