This chapter reports new results from the most recent version of the Global Terrorism Database (GTD), maintained by the National Consortium for the Study of Terrorism and Responses to Terrorism (START) at the University of Maryland. The GTD currently includes data on more than 104,000 terrorist attacks that occurred from 1970–2011.1 The operational definition of terrorism is the threatened or actual use of illegal force by non-state actors, in order to attain a political, economic, religious or social goal, through fear, coercion, or intimidation. Thus, the GTD excludes state terrorism and genocide, topics that are important and complex enough to warrant their own separate reviews.