Pioneer Management

Wm. Stacy Locke, President and Chief Executive Officer
Mr. Locke has served as one of our directors as well as president of the Company since May 1995, when he joined Pioneer. In December 2003, Mr. Locke was appointed chief executive officer. In addition to his continuous role as president, Mr. Locke has also served as our chief financial officer and chief operating officer. Prior to joining Pioneer, Mr. Locke was in investment banking with Arneson, Kercheville, Ehrenberg & Associates from 1993 to 1995 and Chemical Banking Corp. from 1988 to 1992. He worked for Tesoro Petroleum Corp., Valero Energy Corp. and Huffco Petroleum Corp. as a geologist from 1979 to 1986. Mr. Locke received a Bachelor’s Degree in geology from the University of California Santa Barbara and a Master's of Business Administration Degree from Southern Methodist University. 
Lorne E. Phillips, Executive Vice President and Chief Financial Officer
Mr. Phillips was appointed executive vice president and chief financial officer in February 2009. Prior to joining Pioneer, Mr. Phillips worked for 10 years at Cameron International Corp., serving most recently as vice president and treasurer. Prior to that, he was general manager of Cameron's Canadian valves operations, vice president of marketing and M&A for the valves division, and business development manager for Cameron. Before joining Cameron, he was a financial analyst for SCF Partners, a provider of equity capital to energy service and equipment companies, and for Simmons & Company International, an investment bank focused on the energy industry.
Brian L. Tucker, President, Drilling Services
Mr. Tucker was appointed president of our Drilling Services segment effective January 1, 2015. Since joining Pioneer in 2012, Mr. Tucker has served as senior vice president over Appalachia, Utah and North Dakota drilling divisions. Prior to joining Pioneer, Mr. Tucker was a vice president for Helmerich and Payne (H&P), managing its South Texas operations from 2010 to 2012. From 2004 to 2010, he served as drilling engineer and operations manager for the Barnett Shale, South Texas and West Texas operations for H&P. Mr. Tucker served eight years as an officer in the U.S. Army and is a West Point graduate with a Bachelor of Science degree in Systems Engineering.
Carlos R. Peña, Senior Vice President and General Counsel
Mr. Peña has served as senior vice president and general counsel since October 2008. Mr. Peña is corporate secretary and also oversees the compliance function and Health, Safety and the Environment (HSE) Department at Pioneer. Prior to joining Pioneer, Mr. Peña was a general attorney - Mergers & Acquisitions for AT&T from July 2007 to October 2008. From 1996 to 2003, Mr. Peña was a corporate and securities attorney for Vinson & Elkins in Houston and Austin. He came to San Antonio in 2004 and worked in the same capacity for Cox Smith, then joined Fulbright & Jaworski, where he remained until June 2007.
John “Skip” Locken, Vice President Operations, Drilling Services 
Mr. Locken joined Pioneer in 2009 as a North Dakota Division manager after serving as a drilling superintendent with Nabors Drilling USA. In 2014, he was promoted to vice president for the North Region. Mr. Locken has more than 30 years of experience in the drilling industry.
Donald G. Lacombe, Senior Vice President, Marketing Drilling Services
Mr. Lacombe has served as an officer of Pioneer since August 2000. Prior to joining Pioneer, Mr. Lacombe was the contracts and sales manager for Grey Wolf Drilling's South Texas Division and for Flournoy Drilling Co. from April 1993 to August 2000.
Joe Freeman, Senior Vice President, Well Servicing
Mr. Freeman joined Pioneer in 2008 as vice president of Well Servicing and was promoted to senior vice president in 2014. Previously, Mr. Freeman served as vice president of the well servicing division of WEDGE Oil and Gas Services from 2005 to 2008, Gulf Coast Division manager of Key Energy Services from 1998 to 2004, and independent entrepreneur and owner of JPF Well Service from 1987 to 1998, which was sold to Key Energy Services in 1998.
Bill Bouziden, Senior Vice President, Wireline Services and Coiled Tubing Services
Mr. Bouziden joined the Company in 2009 as a Gulf Coast division manager of Wireline Services. In 2013, he was promoted to vice president of Wireline Services and Coiled Tubing Services. In 2014, he was promoted to senior vice president of Wireline Services and Coiled Tubing Services. Mr. Bouziden has served in many capacities during his 32-year career, including Production Services Business Development vice president at Smith International, Inc., president of W-H Energy’s Perf-O-Log, and operations manager at Diamond Wireline.
Scott Keenen, Vice President, Global Human Resources
Mr. Keenen joined Pioneer in 2010. He has 28 years of domestic and international experience across a diverse group of industries, including energy, technology, telecommunications and professional services.  Prior to joining Pioneer, Mr. Keenen was vice president, Global Human Resources, for Premier Research Group, a global contract research organization. Mr. Keenen started his career with Schlumberger Ltd., where he worked for 23 years. Beginning as a cased-hole field engineer working in the Gulf of Mexico, he spent the majority of his Schlumberger career in Human Resources management assignments.  
Pennebaker