Mr. Lawrence is a founder and principal of Yorktown Partners LLC, the manager of the Yorktown group of investment partnerships, which make investments in companies engaged in the energy industry. The Yorktown partnerships were formerly affiliated with the investment firm of Dillon, Read & Co., Inc. where Mr. Lawrence had been employed since 1966, serving as a Managing Director until the merger of Dillon Read with SBC Warburg in September 1997. Mr. Lawrence serves as a director of Crosstex Energy, Inc., Crosstex Energy GP, LLC, Hallador Energy Company, Star Gas Partners, L.P., and Approach Resources, Inc. (each a United States publicly traded company) and Winstar Resources, Ltd., (a Canadian public company) and certain non-public companies in the energy industry in which Yorktown partnerships hold equity interests.