Issues relating to the emergence, persistence, and stability of cooperation among social agents of every type are widely recognized to be of paramount importance. They are also analytically difficult and intellectually challenging. This book, arising from a NATO Advanced Study Institute held at SUNY in 1994, is an up-to-date presentation of the contribution of game theory to the subject. The contributors are leading specialists who focus on the problem from the many different angles of game theory, including axiomatic bargaining theory, the Nash program of non-cooperative foundations, game with complete information, repeated and sequential games, bounded rationality methods, evolutionary theory, experimental approaches, and others. Together they offer significant progress in understanding cooperation.