By Erik Holm 
 

Insurance broker Willis Group Holdings PLC (WSH) said Dominic Casserley will take over as chief executive early next year, replacing Joe Plumeri, the colorful CEO who took the company public in 2001.

The London-based company also elevated Steve Hearn, currently head of one of its main units, to the role of deputy CEO.

Mr. Casserley, 54, is a longtime McKinsey & Co. partner who has led its operations in China and the U.K. Following a transition period in 2013, Mr. Casserley will be based in Willis' New York office.

Mr. Plumeri, 69, will serve as non-executive chairman through July 2013.

With Mr. Plumeri's contract set to expire next July, his potential retirement and the lack of a clear successor had been discussed by analysts for months. In August, Morgan Stanley insurance analyst Gregory Locraft wrote that "the lack of a [contract] renewal or stated successor is a key investor concern."

Willis' lead independent director, former U.S. Senator Bill Bradley, said Mr. Casserley had been selected after a "rigorous and thorough search for our next CEO."

Mr. Hearn, 46, joined Willis when it acquired broker Hilb Rogal & Hobbs in 2008. In January, Mr. Hearn was appointed CEO of Willis Global, the unit that includes the company's global reinsurance and specialty operations. Willis said Mr. Hearn will continue in that role in addition to his duties as deputy CEO.

Mr. Plumeri joined Willis as chairman and CEO in 2000 following a 32-year career with Citigroup Inc. (C) and its predecessors. Willis was then owned by private-equity firm Kohlberg Kravis Roberts & Co. (KKR.XX), and Mr. Plumeri took it public within a year. Shares have risen about 175% since the broker went public at $13.50 a share in June 2001.

Under his tenure, Willis built a flashy new headquarters in London and put its name on the building once known as the Sears Tower in Chicago.

Willis shares, listed on the New York Stock Exchange, were unchanged in light volume in pre-market trading.

Write to Erik Holm at erik.holm@dowjones.com.

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