Cox chief executive Neil Utley is to leave the group and has resigned from his role with immediate effect.
Andrew Fisher, who joins the board with effect from 7 July 2004, will replace Utley.
Fisher joins Cox from CPP Group, where he has been group chief executive since February 2003. Prior to that he was chief executive of Royal Bank of Scotland subsidiary Coutts Group. He is also a non-executive director of Benfield.
Cox chairman Peter Owen said: “Having laid firm foundations upon which to develop our business, we are now ready to exploit the significant opportunities for growth and consolidation that exist in both the underwriting and insurance broking sectors.
“The whole of the Cox Board, including the two principal shareholders represented on it, are enthusiastically supportive of our growth strategy.
“Andrew Fisher is the right person to spearhead this next phase of the company's development. His operational experience and strategic understanding of the changing financial services market make him exceptionally well positioned to lead us in accelerating the pace of growth across the group.
“We would like to express our appreciation to Neil Utley, who has played an important part in the business over the last five years. Cox today is the seventh largest motor insurer and personal lines broker in the UK and it achieved record results last year.
"Neil leaves us in excellent shape to build on our current position.”