Mark McCollum served as president, CEO, and director for Weatherford International plc, a global oilfield service company operating in over 80 countries and employing over 25,000 people, from April 2017 until June 2020.  
Prior to joining Weatherford, McCollum served as executive vice president and chief financial officer for Halliburton, also a global oilfield service company, from December 2007 until March 2017. During that time, he also served in an interim role from December 2014 to July 2016 as executive vice president and chief integration officer during the pendency of Halliburton’s proposed acquisition of Baker Hughes. He also served as senior vice president and chief accounting officer for Halliburton from 2003 to 2007.

Prior to joining Halliburton, McCollum served in various senior executive positions for Tenneco from 1995 through 2003. Before joining Tenneco, he spent 14 years with Arthur Andersen LLP and served as an audit and business advisory partner of the firm’s worldwide partnership from 1991 through 1994. 

McCollum currently serves on the board of directors for Marathon Oil Corp., Westlake Corp., and Seadrill Limited plc. He is a former member of the board of directors of Archrock Inc. and Butler Manufacturing. McCollum is also a member of the board of trustees for the Baylor College of Medicine, the board of directors for the Baylor St. Luke’s Medical Center joint venture, and the board of directors of Yellowstone Schools. 

McCollum earned a bachelor of business administration in accounting from Baylor University in 1980 and became licensed as a certified public accountant in Texas in 1982. A former regent, he remains actively involved with the university, currently serving as chair of Baylor’s NIL Advisory Council and as a member of the board of advocates for Baylor’s School Engineering and Computer Science.

McCollum and his wife, Jennifer, currently reside in Waco, Texas. They have two grown children, a daughter-in-law, and four grandchildren.