Mr. Walker was named Chairman of the Board of the Company in May 2013, in addition to the role of Chief Executive Officer and director, both of which he assumed in May 2012, and the role of President, which he assumed in February 2010. He previously served as Chief Operating Officer from March 2009 until his appointment as Chief Executive Officer. He served as Senior Vice President, Finance and Chief Financial Officer from September 2005 until March 2009. Mr. Walker is a director of the Houston Branch of the Dallas Federal Reserve. He is also on the Board of Trustees for the Houston Museum of Natural Science, a member of the Business Council, the Business Roundtable, All-American Wildcatters, and serves as a director of the American Petroleum Institute (Executive Committee) and America’s Natural Gas Alliance (Executive Committee). In addition to his current directorships of public companies noted in the box to the right, in the past five years he also served on the boards of Western Gas Equity Holdings, LLC and Western Gas Holdings, LLC, both of which are subsidiaries of Anadarko, and on the board of Temple- Inland, Inc.