The scientific study of international events has been revolutionized. Writers have long viewed such phenomena as war and peace, conflict and cooperation, as sequences of events—démarches, protests, treaties, crises, armed interventions, conferences, and other occurrences that stand out against the gray background of everyday living. New thinking, however, has given us a more systematic means of analyzing the occurrence of events and of understanding and even predicting the international processes they influence. This book offers insight into the current exploration of a modern and sophisticated analytic and methodological approach to the study of interactions among nation-states, ethnic groups, and other international actors.National Science Foundation support brought together key event-data researchers in Data Development for International Research (DDIR) to assess needs and consider alternative approaches. DDIR has sought to advance the quantitative analysis of international politics. In Phase I it updated, expanded, and developed new national attribute and international conflict data. DDIR Phase II, represented in this book, has two main goals: to systematically enhance and improve currently existing, high-quality event data sets and to develop computer software that can facilitate the future generation of such event data and make data sets more readily accessible to users.