The authors, two of the most prominent game theorists of this generation, havedevoted a number of years to the development of the theory presented here, and to its economicapplications. They propose rational criteria for selecting one particular uniformly perfectequilibrium point as the solution of any noncooperative game. And, because any cooperative game canbe remodelled as a noncooperative bargaining game, their theory defines a one-point solution for anycooperative game as well.By providing solutions - based on the same principles of rational behavior- for all classes of games, both cooperative and noncooperative, both those with complete and withincomplete information, Harsanyi and Selten's approach achieves a remarkable degree of theoreticalunification for game theory as a whole and provides a deeper insight into the nature ofgame-theoretic rationality.The book applies this theory to a number of specific game classes, suchas unanimity games; bargaining with transaction costs; trade involving one seller and severalbuyers; two-person bargaining with incomplete information on one side, and on both sides. The lastchapter discusses the relationship of the authors' theory to other recently proposed solutionconcepts, particularly the Kohberg-Mertens stability theory.John C. Harsanyi is Flood ResearchProfessor in Business Administration and Professor of Economics, University of California, Berkeley.Reinhard Selten is Professor of Economics Institute of Social and Economic Sciences: University ofBonn, Federal Republic of Germany.

When John Harsanyi came to Stanford University as a candidate for the Ph.D., I asked him why he was bothering, since it was most un likely that he had anything to learn from us. He was already a known scho lar; in addition to some papers in economics, the first two papers in this vol ume had already been published and had dazzled me by their originality and their combination of philosophical insight and technical competence. However, I am very glad I did not discourage him; whether he learned any thing worthwhile I don't know, but we all learned much from him on the foundations of the theory of games and specifically on the outcome of bar gaining. The central focus of Harsanyi's work has continued to be in the theory of games, but especially on the foundations and conceptual problems. The theory of games, properly understood, is a very broad approach to social interaction based on individually rational behavior, and it connects closely with fundamental methodological and substantive issues in social science and in ethics. An indication of the range of Harsanyi's interest in game the ory can be found in the first paper of Part B -though in fact his owncontri butions are much broader-and in the second paper the applications to the methodology of social science. The remaining papers in that section show more specifically the richness of game theory in specific applications.