Beth S. Perlman will join Constellation Energy Group as vice president and chief information officer. Prior to her appointment, Perlman had been vice president of Enron Wholesale Trading Technology. She began her career with Enron in 1995 as Director, Risk Management Administration.

Jean H. Gibson will replace Frank Boyle as chief financial officer of Central Vermont Public Services. She has most recently served as vice president of the Exelon Corporation.

Hanover Compressor has appointed Mark S. Berg Senior Vice President and General Counsel. Berg has acted as executive vice president and general counsel for American General Corporation over the last five years.

Richard T. Ashbeck has been promoted to the position of vice president-treasurer of energy and communications company Black Hills Corporation. Ashbeck, who joined Black Hills in July 2000, had previously been employed as Chief Financial Officer by Indeck Capital, Inc., an independent power company which was later acquired by Black Hills.