Jack S. Levy is Board of Governors' Professor of Political Science at Rutgers University, President of the International Studies Association (2007-2008), and author of War in the Modern Great Power System 1495-1975. He has also written numerous articles on the causes of war and on decision-making.Gary Goertz is Professor of Political Science at the University of Arizona. He is the author or co-author of five books and over 25 articles on issues of methodology, international institutions, and conflict studies, including "Necessary Conditions: Theory, Methodology, and Applications," (2003 Rowman & Littlefield) and "Social Science Concepts: A User's Guide" (2006 Princeton University Press).

• 1. Introduction 2. Causal Explanation, Necessary Conditions, and Case Studies 3. The Role of Necessary Conditions in the Outbreak of World War I 4. Contingency, Catalysts and Non-Linear Change: The Origins of World War I 5. Powder Kegs, Sparks and World War I 6. Necessary Conditions and World War I as an Unavoidable War 7. Power, Globalization, and the End of the Cold War: Reevaluating a Landmark Case for Ideas 8. Perestroika without Politics: How Realism Misunderstands the Cold War’s End 9. New versus Old Thinking in Qualitative Research 10. Conclusions

Giovanni Sartori Award for the Best Book Published in 2007 Developing or Applying Qualitative Methods - Honorable Mention'...an impressive collection of essays that survey the ways in which necessary conditions counterfactuals are used in the logics of causal explanation, particularly in explanations of international conflict. The work represents an important contribution to the study of methods in general and usefully develops some central concepts in qualitative research. The substantive focus also helps to elucidate the more abstract theoretical discussions.'Newsletter of the American Political Science Association