Deterministic approaches identify the so-called root causes of terrorism, variables of a higher order which would necessarily and in general be responsible for the emergence of terrorism in various countries and regions around the world and at various points in time. Furthermore, given the pronounced structural nature of this approach, organizational agency does not play a role here. That said, most analyses do make reference to organizations, if only to assign labels and classify terrorist acts in data sets. This chapter starts off with the classification of root causes of terrorism in structural, facilitator, motivational, and triggering causes and discusses studies which have tested some of the root causes included there.