Preface to Volume 1 (K. Arrow, A. Sen, K. Suzumura). In troduction (K. Suzumura). Part 1: Arrovian Impossibility Theorem s. 1. Impossibility theorems in the Arrovian framework< /STRONG> (D. Campbell, J. Kelly). Introduction. Definitions and framewor k. Fundamental Lemmas and Arrows’s theorem. Relaxing the Pareto criterio n. Relaxing transitivity. Relaxing the domain condition. Relaxing indepe ndence of irrelevant alternatives. Modifications of the Arrovian framewo rk. Concluding remarks. 2. Categories of Arrovian Voting Schemes (F. Aleskerov). Introduction. Voting: A general description. R ationality of individual opinions and collective decisions. Social decis ion rules. Functional voting rules. Social choice correspondences. Concl usion. 3. Domain Restrictions (W. Gaertner). Introducti on. Notation and definitions. The existence of collective choice rules u nder exclusion conditions for finite sets of discrete alternatives. The existence of Arrovian social welfare functions and the domain of the sim ple majority rule. Distributional restrictions over the set of individua