The formal theory of bargaining originated with John Nash's work in the early 1950s. This book discusses two recent developments in this theory. The first uses the tool of extensive games to construct theories of bargaining in which time is modeled explicitly. The second applies the theory of bargaining to the study of decentralized markets.Rather than surveying the field, the authors present a select number of models, each of which illustrates a key point. In addition, they give detailed proofs throughout the book.