Mark Lyons takes on new responsibilities at Arch Capital.

Arch Capital Group Ltd. has named Mark Lyons president and chief operating officer of Arch Insurance Group (U.S.).

Lyons is responsible for each of the underwriting units of Arch's U.S.-based insurance operations. He reports to Ralph Jones, chairman and chief executive officer of Arch Worldwide Insurance Group.

"Mark has been instrumental in the formation of our insurance group and has worked tirelessly to build the foundation that supports our insurance operations during the last four years. His promotion is a well-deserved recognition of his substantial value to our company, "Jones said in a statement.

Lyons' plans include an increase in internal training and education: "I plan to focus on continually advancing our market-cycle management framework, which is already quite extensive. Ralph Jones and I are putting a premium on product development efforts and in increasing our internal education and training capabilities. I also have the luxury and privilege of working with some of the best underwriting executives in the industry.

This team will continually focus on providing quality earnings to boost our book value; he said.

Lyons joined Arch Insurance Group as senior vice president and chief actuary in August 2002, and in 2003 he was named executive vice president of group operations and chief actuary.