Aon, a provider of risk management, insurance and reinsurance brokerage services, has appointed Lester Knight, an independent director since 1999, as its non-executive chairman.

Mr Knight succeeds Patrick Ryan, Aon’s executive chairman and founder, who previously announced his intention to retire on August 1, 2008.

Mr Knight is a founding and managing partner of RoundTable Healthcare Partners, a healthcare-focused private equity investment firm. Prior to RoundTable, he was the chairman and CEO of Allegiance.

Andy McKenna, Aon’s lead director and chair of the ad hoc nominating committee, said: Aon’s choice of an independent non-executive chairman is consistent with best governance practices of leading global firms. The Aon family and our shareholders should be confident in Lester’s ability to sustain the independent oversight of their interests.