Dennis Mahoney and Steve McGill have been appointed the chairman and chief executive of Aon's new business unit — Aon Global.

Aon Global represents an amalgamation of a number of Aon's businesses, including its Global Large Corporate business unit, Captives Services Group, International Risk Management Group (IRMG), Risk Consulting and Risk Engineering business units.

Mahoney will relocate to Bermuda to drive the placement of Aon's worldwide services.

Greg Case, president and chief executive, Aon Corporation, said: “Our broking and placement capabilities are a cornerstone of client service. Dennis' leadership and experience are unmatched in the industry.

"By being in Bermuda, leading the co-ordination and placement of major and complex risks for the world's largest companies, Aon can leverage his world-class broking skills on a global scale, where they can have the most significant impact on client value.”

Chief executive of Aon Holdings Australia, Peter Harmer, has been named as Mahoney's replacement in the roles of chief executive, Aon Ltd and country manager for Aon UK.

Mahoney will continue to serve as chairman, Aon Ltd to assist and ensure a successful leadership transition, and will then be succeeded by McGill, who will serve as non-executive chairman, Aon Ltd.

In addition, Jonathan Palmer-Brown, chairman, Specialty Global Industries, has been appointed deputy chairman of Aon Ltd.

Case said: “Peter is an exceptional, results-oriented leader with an outstanding track record in Australia, where he grew business and achieved results at every stage in his career.

"Under Peter's stewardship, the Aon businesses in Australia have strengthened their market position through a unified strategy and an integrated approach to developing client solutions.

“With the support of Steve, a 27-year veteran of the London marketplace, and Jonathan, also a long-standing figure in the London market, Peter and his leadership team will be able to write the next chapter for Aon in the UK, ensuring that all the company's resources in the UK are combined and deployed to maximum effect, connection with the global network and even greater success in retail.

“By focusing on recruiting and retaining high quality professionals, and driving organisational flexibility and productivity, I am confident this leadership team will continue to deliver distinctive value and impact to clients every day.”