Paramilitary violence in Bosnia and Herzegovina during the 1992-1995 war was pervasive. Virtually every book written on the conflict discusses paramilitary units, but much about them remains unknown. Local comparisons are sparse, and it is still poorly understood why in some towns civilians were beaten and shot, while in others they were raped and set alight. The archives of the International Criminal Tribunal for the former Yugoslavia (ICTY) in The Hague enable careful investigation of thousands of documents and testimonies, showing how and why paramilitaries engaged at the local level. This comparative study focuses on two towns that experienced significant paramilitary violence, Bosanski Šamac and Višegrad, arguing that there were structural reasons driving differences in the perpetration.