Stewart I. Donaldson is Professor and Director of the Claremont Evaluation Center, and Dean of the Schools of Social Science, Policy & Evaluation and Community & Global Health at Claremont Graduate University. Dean Donaldson continues to develop and lead one of the most extensive and rigorous graduate programs specializing in evaluation. Dr. Donaldson is currently serving as the Director of the American Evaluation Association's (AEA) Graduate Education Diversity Internship (GEDI) Program and recently served a 3-year term on the AEA Board. He leads the Certificate for the Advanced Study of Evaluation Program at Claremont (a distance education program for working professionals) and has taught thousands of graduate students and working professionals participating in online courses, workshops, webinars, and various other e-learning experiences. He is a fellow of the Western Psychological Association, serves on the Boards of the International Positive Psychology Association and EvalPartners, and the Editorial Boards of the American Journal of Evaluation, New Directions for Evaluation, Evaluation and Program Planning, and the Journal of Multidisciplinary Evaluation. Professor Donaldson has authored or co-authored more than 200 evaluation reports, scientific journal articles, and chapters and his recent books include Credible and actionable evidence: The foundation of rigorous and influential evaluations (this volume); Practical program design and redesign: A theory-driven approach to program development and developmental evaluation (forthcoming); Evaluation for an equitable society (forthcoming); Theory-driven positive psychology: A culturally responsive scientific approach (forthcoming); Emerging Practices in International Development Evaluation (2013); The Future of Evaluation in Society: A Tribute to Michael Scriven (2013); Teaching Psychology Online: Tips and Strategies for Success (2012); Social Psychology and Evaluation (2011); Advancing Validity in Outcome Evaluation: Theory and Practice (2011); Applied Positive Psychology: Improving Everyday Life, Health, Schools, Work, and Society (2011); What Counts as Credible Evidence in Applied Research and Evaluation Practice? (2008); Program Theory-Driven Evaluation Science: Strategies and Applications (2007); Applied Psychology: New Frontiers and Rewarding Careers (2006); and Evaluating Social Programs and Problems: Visions for the New Millennium (2003). Dr. Donaldson has been honored with Early Career Achievement Awards from the Western Psychological Association and the American Evaluation Association. In 2013, he was honored with the American Evaluation Association's Paul F. Lazarsfeld Award for sustained lifetime written contributions to advancing evaluation theory and practice, and was elected President of the American Evaluation Association. Christina A. Christie is a Professor and Head of the Social Research Methodology Division in the Graduate School of Education and Information Studies at University of California, Los Angeles. Christie specializes in educational and social policy and program evaluation. Her research focuses on the factors and conditions that influence evaluation practice in an effort to strengthen our understanding of evaluation as a method for facilitating social change. She has published extensively and her work appears in journals such American Journal of Evaluation, Children and Youth Services Review, Evaluation and Program Planning, Studies in Educational Evaluation and Teachers College Record. Christie has served on the board of the American Evaluation Association (AEA) and is the former Chair of the Theories of Evaluation Division and the Research on Evaluation Division of AEA. Currently, she is an Associate Editor for the American Journal of Evaluation. Melvin M. Mark is professor of psychology at the Pennsylvania State University, where he also is Head of the Department of Psychology. He has served as President of the American Evaluation Association (AEA). He was Editor of the American Journal of Evaluation (and is now Editor Emeritus). A social psychologist, Dr. Mark has wide ranging interests related to the theory, methodology and practice of evaluation, as well as a general interest in the application of social psychology to evaluation and applied social research. Dr. Mark's awards include the American Evaluation Association's Lazarsfeld Award for Contributions to Evaluation Theory. He is author of more than 125 articles and chapters in books. Among his books are Evaluation: An integrated framework for understanding, guiding, and improving policies and programs and the co-edited volumes Social Science and Social Policy; SAGE Handbook of Evaluation; What Counts as Credible Evidence in Applied Research and Evaluation Practice; Evaluation in Action: Interviews with Expert Evaluators; and Social Psychology and Evaluation.