H.R. ""Hal"" Warner, Jr., SPE, is a consulting reservoir engineer. Previously, he worked for 27 years for ARCo, ending as a Senior Technical Advisor; since 2000, he has been an independent consultant and has spent much of his time during the past decade consulting through DeGolyer and MacNaughton. Warner is an SPE Distinguished Member and received the 1979 AIME Rossiter W. Raymond Award. He has written many SPE technical papers and served as Executive Editor of SPE Reservoir Engineering (1992-1994) and on the JPT Special Series Committee (2004-2012). He is the author or coauthor of three chapters in SPE's Petroleum Engineering Handbook (2007) and served as editor of the Emerging and Peripheral Technologies volume; he is also the coauthor of SPE's Low Invasion Coring monograph. Warner holds a BS degree from Iowa State University and a PhD degree from the University of Wisconsin, both in chemical engineering.