This book provides an innovative foundation for looking at human and social behavior as a system of purposeful (teleological) events. It uses a systems theoretical approach for the study of these phenomena, and illustrates and extends general systems theory. <br><br>Part One develops the concepts of traditional mechanism from which, successively, the concepts of "function," "choice," "goal-seeking," and "purposefulness" are derived, leading to a quantitative formulation of "personality". Part Two provides an analysis of aspects of purposeful behavior and personality, and Part Three explores the interaction of purposeful systems. Part Four is concerned with the study of social groups and ideal-seeking behavior. Finally, structural concepts underpinning the theoretical system are redefined in technological terms, thus demonstrating the non-vicious circularity and interdependence of all scientific concepts. <br><br>"What makes this book magical' is that Ackoff provides operational definitions' for many ill-defined words and concepts--from defining knowledge' and understanding' to providing definitions of feelings/emotions.... In terms of Kuhn's idea of paradigm shifts'--this book represents a shift that has yet to be appreciated, thirty years later." --W. Curtiss Priest, Massachusetts Institute of Technology <br><br><i>Russell L. Ackoff </i> is chairman of the board of the Institute for Interactive Management. Since 1986 he has been the Anheuser-Busch Professor Emeritus of Management Science, The Wharton School, University of Pennsylvania. He is also the Anheuser-Busch Visiting Professor of Marketing, Olin School of Business, Washington University, St. Louis. He was former chairman of the Social Systems Science Department and the Busch Center, which specializes in systems planning, research, and design. Dr. Ackoff is the author and co-author of nineteen books. <br><br><i>Fred E. Emery </i> was Senior Research Fellow at the Australian National University, Canberra. Previously he was chairman of the Human Resources Centre at the Tavistock Institute, and a fellow at the Center for Advanced Studies in the Behavioral Sciences, Palo Alto. <br><br> <i>Brent D. Ruben</i> is professor of communication and executive director, Center for Organizational Development and Leadership at Rutgers University.