Preface to Volume 1 (K. Arrow, A. Sen, K. Suzumura). Introduction (K. Suzumura). Part 1. Arrovian Impossibility Theorems. 1. Impossibility theorems in the Arrovian framework (D. Campbell, J. Kelly). 2. Categories of Arrovian voting schemes (F. Aleskerov). 3. Domain restrictions (W. Gaertner). Part 2. Voting Schemes and Mechanisms. 4. Voting procedures (S. Brams, P. Fishburn). 5. Implementation theory (E. Maskin, T. Sjostrom). 6. Axiomatic cost and surplus-sharing (H. Moulin). Part 3. Structure of Social Choice Rules. 7. Positional rules of collective decision-making (P. Pattanaik). 8. Game-Theoretic Analysis of voting in committees (B. Peleg). 9. Representative democracy and social choice theory (N. Schofield). Part 4. Welfare, Justice and Poverty. 10. Social welfare functionals and interpersonal comparability (C. d'Aspremont, L. Gevers). 11. Utilitarianism and the theory of justice (C. Blackorby, W. Bossert, D. Donaldson). 12. Inequality, poverty and welfare (B. Dutta).