Marsh & McLennan Companies Inc. announced that Brian Duperreault, 65, will retire as the company’s president and chief executive officer at the year’s end.

Daniel S. Glaser, 52, currently the company’s group president and chief operating officer, has been named Duperreault’s successor and will become president and chief executive officer effective January 1, 2013.

Upon his retirement as president and chief executive officer, Duperreault will also retire from the company’s board of directors. Glaser will join the board as a director effective Jan. 1, 2013.

“I am proud of what we have accomplished, largely due to the efforts of our leadership team and our dedicated colleagues around the world. Being part of the turnaround of Marsh & McLennan Companies has been one of the most gratifying aspects of my career,” Duperreault said.

Duperreault is an insurance industry veteran who, over the span of his nearly 40-year career, has held top leadership roles at various firms. Prior to his role with Marsh & McLennan Companies, he wasCEO of ACE Limited and a member of that company’s board of directors. Duperreault also served in senior executive positions with AIG and its affiliates.

Duperreault currently serves as chairman of the Federal Advisory Committee on Insurance (FACI). Marsh & McLennan told Insurance Journal that Duperreault will remain with FACI after his retirement. He was also inducted into the International Insurance Society’s Hall of Fame in 2011.

Glaser, who will lead Marsh & McLennan beginning next year, has served as group president and chief operating officer of Marsh & McLennan Companies since April 2011, with strategic and operational oversight of both the Risk and Insurance Services and the Consulting segments of the company.

Prior to his current role, Glaser served as chairman and CEO of Marsh Inc. He rejoined Marsh in December 2007, after serving in senior positions in commercial insurance and insurance brokerage in the United States, Europe, and the Middle East. He began his career at Marsh 30 years ago.