This book extrapolates on the Nash (1950) treatment of the bargaining problem to consider the situation where the number of bargainers may vary.This book extrapolates on the Nash (1950) treatment of the bargaining problem to consider the situation where the number of bargainers may vary. The authors formulate axioms to specify how solutions should respond to such changes and provide new characterizations of all the major solutions as well as the generalizations of these solutions.This book extrapolates on the Nash (1950) treatment of the bargaining problem to consider the situation where the number of bargainers may vary. The authors formulate axioms to specify how solutions should respond to such changes and provide new characterizations of all the major solutions as well as the generalizations of these solutions.This book extrapolates on the Nash (1950) treatment of the bargaining problem to consider the situation where the number of bargainers may vary. The authors formulate axioms to specify how solutions should respond to such changes, and provide new characterizations of all the major solutions as well as the generalizations of these solutions.Acknowledgments; 1. Preliminaries; 2. Axiomatic theory of bargaining with a fixed number of agents; 3. Population monotonicity and the Kalai-Smorodinsky solution; 4. Population monotonicity and the egalitarian solution; 5. Truncated egalitarian and monotone path solutions; 6. Guarantees and opportunities; 7. Stability and the Nash solution; 8. Stability without pareto-optimality; 9. Stability and the leximin solution; 10. Population monotonicity, weak stability and the egalitarian solution; 11. Stability and collectively rational solutions; 12. Invariance under replication and juxtaposition; Bibliography; Index. This is one of the best books ever written on normative collective choice. Ehud Kalai, Social Choice and Welfare For both he sympathetic and the critical reader, the well-written monograph is the reference boolCZ