Comparative research on the determinants of genocide has surged in recent years, as reflected in the six books under review. The new research makes genocide studies more systematic and theoretical; integrates the topic into mainstream social science disciplines; points to three emerging explanatory paradigms; and yields some surprising cumulative findings. However, the works also reveal significant conceptual, empirical, and methodological problems that limit the comparative enterprise and the search for a general theory. The article argues for an alternative, disaggregated approach that situates genocide within a spectrum of organized violence against civilians and links genocide studies to studies of violence in war.