Throughout the history of humankind, people have struggled for rights and freedom, and have used different strategies to reach their goals. Furthermore, in recent times, terrorism is overly interpreted to mean a reaction by Muslim populations against Western countries, implying the actions are driven along religious lines and seek to restore freedom. Extreme actions following perceived persecution or extreme distress are well established, not only in the form of terrorism, but also violence more generally and, at times, in the form of suicide. For example, Durkheim postulated a relationship between the degree of social integration and suicide rates. Both religious suicide bombing and apocalyptic suicide represent a final cosmic war in which violence is sanctioned to rid the world of evil forces. In this chapter we describe some the factors that may contribute to acts of violence and terrorism in groups and as lone actors. We explore the reasons why second- and third-generation migrants are much more likely to participate in such activities. These may be related to a sense of alienation, exposure to religious fundamentalism in the absence of religious literacy and connection with orthodox sources, failure to adapt, and a lack of resistance to persuasion into violence. Some preventive strategies are described. We also consider radicalism processes by which an individual or a group carries out violent actions connected to an extremist ideology, and consider modern radical groups, which are now less organized and centralized than previous hierarchical movements such as Al-Qaeda.