Jeff Joireman, PhD, was originally trained in social psychology and has held positions in departments of psychology and marketing. Dr. Joireman is currently an associate professor of marketing at Washington State University, where he teaches consumer behavior and marketing research and serves as the department's PhD coordinator. Dr. Joireman's research has addressed a wide range of topics, and his articles have drawn on many of the paradigms detailed in this book. He has published more than 60 articles and book chapters in psychology and marketing, with many of his publications appearing in the fields' leading journals, including the Journal of Personality and Social Psychology, Personality and Social Psychology Bulletin, the Journal of Applied Psychology, Organizational Behavior and Human Decision Processes, the Journal of International Business Studies, the Journal of Retailing, and Marketing Letters. In 2005, Dr. Joireman coedited a book with Alan Strathman titled, Understanding Behavior in the Context of Time: Theory, Research, and Application. He has also reviewed more than 200 articles for more than 25 different journals, served on the editorial boards for the Journal of Personality and Social Psychology, Psychological Science, the Journal of Environmental Psychology, and Group Dynamics, and has twice been named the Journal of Environmental Psychology's Most Prolific Reviewer. Dr. Joireman has won numerous honors and awards, including a Fulbright Scholarship to the Netherlands, multiple Dean's Excellence Awards, an Outstanding Faculty Service Award, and the Department of Marketing's Professor of the Year Award. Paul A. M. Van Lange, PhD, is professor of social psychology and chair of the Department of Social and Organizational Psychology at the VU University at Amsterdam, the Netherlands, and holds a position as Distinguished Research Fellow at the University of Oxford in England. Most of his research on human cooperation and trust is grounded in interdependence theory, through which he seeks to understand the functions of forgiveness, generosity, empathy, fairness, retaliation, and competition, as well as general beliefs of human nature in various situations. He has published influential papers that have appeared in journals such as the Annual Review of Psychology, Psychological Bulletin, and Journal of Personality and Social Psychology. With various colleagues around the globe, Dr. Van Lange has published several books, including the Atlas of Interpersonal Situations (Kelley et al., 2003), Bridging Social Psychology (Van Lange, 2006), the Handbook of Theories of Social Psychology (Van Lange, Kruglanski, & Higgins, 2012), Social Dilemmas: The Psychology of Human Cooperation (Van Lange, Balliet, Parks, & Van Vugt, 2014), and Power, Politics, and Paranoia (Van Prooijen & Van Lange, 2014). He has served as associate editor for various journals, including the European Journal of Social Psychology, the Journal of Personality and Social Psychology, and Psychological Science, and is founding editor of an edited interdisciplinary series on Social Dilemmas (Van Lange, Rockenbach, & Yamagishi, 2014). He has been a director of the Kurt Lewin Institute, has been president of the Society of Experimental Social Psychology, and has supervised more than 20 PhD students and five postdoctoral students. Dr. Van Lange's scientific work has been supported by numerous grants and was recognized by the Kurt Lewin Award from the European Association of Social Psychology (2014).