This analysis of the psychology of revolution has adopted a “from societies to cells” approach, where macro processes are given priority. However, micro-level factors such as individual-level personality traits also have an important role in revolutions. In this chapter, an assessment is made of the personality characteristics of revolutionary leaders, people who surround the revolutionary leader, the lay masses who follow and support the extremist revolutionary leader, and those who do not conform and obey according to the wishes of the revolutionary regime. The traditional research focus has been on the revolutionary leader, and in this analysis the key traits of these leaders are identified as Machaivellianism, pathological narcissism, craving for power, risk-taking, intolerance for ambiguity, illusions of control and grandeur, and charisma. The personality of the extremist revolutionary leader in particular shapes what happens after regime change. Typically, moderates get pushed aside and extremists take over, with radical programs such as the “Cultural Revolution” (as in China and Iran).