For the past 40 years, researchers studied the relationship between mental disorder and terrorist involvement. The literature developed in 4 paradigms, each of which differs in terms of their empirical evidence, the specific mental disorders studied, and their conceptualizations of terrorist involvement. These paradigms have not, however, witnessed linear and incremental improvements upon 1 another. Although 1 paradigm has generally tended to dominate a temporal period, many false assumptions and incorrect interpretations of earlier work permeate into today’s discourse. This article provides a history of the study of mental disorders and the terrorist. First, we briefly outline the core fundamental principles of the first 2 paradigms, The article then outlines the core arguments produced by the seminal reviews conducted in Paradigm 3. We highlight how these findings were consistently misinterpreted in subsequent citations. We then highlight recent innovations in the study of terrorism and mental disorder since the various influential literature reviews of 1997–2005. We conclude by outlining how future research in this area may improve in the coming years by broadening our understanding of both terrorist involvement and psychopathology away from simple dichotomous thinking.