In writing about "The Political Terrorist," Pearce (1977) claimed that the political terrorist's "behavior may show some evidence of psychopathy, paranoia, or other psychiatric lacunae." He reasons that "This individual may be an aggressive psychopath, who has espoused some particular cause because extremist causes can provide an external focal point for all the things that have gone wrong in his life." In a study of terrorist personality types, Johnson and Feldman (1992) argued that "In a sense, many terrorists may be viewed as people with marginal personalities who are drawn into the group by their own self deficiencies....Personalities with paranoid, antisocial, and sadomasochistic tendencies would also be drawn to the violence fostered by terrorism." In addition, there is often a direct or implied association between pathology and terrorism. In challenging these arguments on a theoretical basis, it can be argued that terrorists are singled out as being mentally ill because they engage in violent acts that are viewed as threatening by established state institutions and actors; however, these same state institutions mount military forces that engage in violence, death, and atrocities against perceived enemies. Such behavior is not deemed to be the product of mental illness. On the empirical level, evidence from life histories and recruitment of various terrorists and terrorist groups have found that although there is no homogeneous psychological pattern, they tend to come from relatively "normal" backgrounds. Social learning, situational group pressure, fervently held ideologies, and other behavioral conditioning apparently explain the behaviors of most terrorists. This article argues, however, that there may be evidence that links the long-term engagement of individuals in terrorist activity with subsequent mental health problems, provided certain factors are present. Certain stressors that occur because of terrorist activity may result in psychological disturbance in certain terrorist. These factors may partially explain the instability of terrorist groups and should be taken into account when detaining and interrogating terrorist suspects. 12 notes and 87 references