Margrett to succeed Bucknall at Willis Ltd.

LONDON—Willis Group Holdings Ltd. said Thursday that David Margrett, chief executive officer of the broker's Global Specialities unit, will take on the additional roles of chairman and CEO of U.K. unit Willis Ltd. upon the retirement of Richard Bucknall at the end of March.

Mr. Bucknall, who also serves as vice chairman of Willis Group, will remain with broker in an advisory role until the end of the year, Willis said in a statement. "It has been an enormous privilege and my distinct honor to have spent the last 21 years of my career at Willis and the last six under the leadership and direction of (Willis Group CEO) Joe Plumeri," Mr. Bucknall said in a statement.