Contributing Authors. Preface. 1. The Consequences of International Regimes; O.R. Young. I: Simple Effectiveness. 2. Methodological Challenges in the Study of Regime Effectiveness; A. Underdal. 3. Case Studies of the Effectiveness of International Environmental Regimes; S. Andersen, J. Wettestad. 4. Causal Mechanisms and the Study of International Environmental Regimes; J. Hovi. 5. Boolean Analysis, Mechanisms and the Study of Regime Effectiveness; O. Schram Stokke. 6. A Quantitative Approach to Evaluating International Environmental Regimes; R.B. Mitchell. 7. Formal Theory and Regime Effectiveness: Rational Players, Irrational Regimes; H. Ward, F. Grundig, E. Zorick. 8. Does Regime Robustness Require a Fair Distribution of the Gains from Cooperation? A. Hasenclever, P. Mayer, V. Rittberger. II: Broader Consequences. 9. Methodological Issues in the Study of Broader Consequences; T. Gehring. 10. Exploring Regime Interaction; T. Gehring, S. Oberthür. 11. International Regimes and Democracy; H. Breitmeyer. 12. Into the Methodological Void; G. Walter, M. Zürn. 13. Regimes and Social Transformation; B.B. Hughes. III: Conclusion. 14. Research Strategies for the Future; A. Underdal, O.R. Young.