“He started life as an actuary and went beyond being an actuary to [become] a very senior executive.“

That’s the simple sentence that Maurice “Hank” Greenberg, former chairman and CEO of American International Group and current chair and CEO of C.V. Starr & Co., used to sum up Brian Duperreault’s career in the opening of a video filmed in connection with Duperreault’s induction into the Insurance Hall of Fame in 2011—an honor presented annually by the International Insurance Society.

A biography on the Hamilton Insurance Group website notes that the senior roles have included:

• Executive positions with AIG and its affiliates from 1978 to 1994.
• CEO of ACE Ltd. from October 1994 through May 2004; president from October 1994 through November 1999; nonexecutive chairman from May 2004 through December 2007.
• President and CEO of Marsh & McLennan Cos. from January 2008 until December 2012.

More expansive biographies, including one on the Hall of Fame website, detail Duperreault’s accomplishments in those positions:

• Starting his career as an actuary at AIG in 1973, he ultimately became chairman and CEO of AIG’s international arm, American International Underwriters.
• Transforming ACE from a 50-employee boutique operation that wrote only two lines of insurance into an international insurance and reinsurance “powerhouse” with more than 9,000 employees, writing a wide variety of lines in almost 50 countries.
• Accomplishing much of ACE’s transformation through acquisitions, including the big one—a $3.5 billion deal for the P/C business of CIGNA in 1999—as well as prior deals for property-catastrophe reinsurers Tempest Re (1996) and CAT Ltd. (1998), acquisitions of Lloyd’s managing general agencies, and even a political risk insurance venture along the way.
• Rebuilding the morale and reputation of MMC after a N.Y. attorney general’s 2004 investigation into insurance industry commission practices; implementing greater expense discipline and ultimately growing the broker through acquisition; and establishing Marsh & McLennan Agency, aimed at serving small and emerging U.S. companies.

Beyond that, the Hall of Fame biography suggests that Duperreault was “instrumental in transforming Bermuda from an island nation with a small, reinsurance-focused market into a global insurance center.”

According to the biography on Hamilton Insurance Group’s website, in addition to being CEO of the group today, Duperreault is also a member of the boards of the International Insurance Society, the IESE Business School and the Insurance Information Institute, and serves as the lead director of Tyco’s board.

He also serves as chairman of the Federal Advisory Committee on Insurance, the Board of Overseers of the School of Risk Management of St. John’s University and the Bermuda Institute of Ocean Sciences.

He has a bachelor’s degree in mathematics from Saint Joseph’s University and achieved his designation as an Associate of the Casualty Actuarial Society in 1975, according to the CAS.