ABSTRACT The late David C. Rapoport’s seminal “Four Waves of Modern Terrorism” model has exerted huge influence over approaches to historical and contemporary terrorism. Structuring the history of terrorism since the 1870s into four successive “waves”, the model purports to explain the origin, duration, and end of terrorist episodes, as well as the persistence of terrorism over the longue durée. Close examination of successive elaborations of the model reveals flaws and contradictions that undermine the theory itself. Most significantly, its central contention that terrorist waves follow a generational pattern is underdeveloped and under-evidenced. Such inherent weaknesses call into question the model’s usefulness. Consequently, the article argues that terrorism studies scholars should discard the model in favour of genuine historical study of terrorism in the past.