Two explanations, instrumental and organizational, of terrorist behaviors are proposed. An analysis of memoirs of members of terrorist groups over the past 100 years is presented. The effects of internal tensions within the Front de Liberation du Quebec on the group's activities also are discussed. Idealogical, political, social, and cultural factors that influence terrorist ideologies and actions are examined in case studies of terrorist groups in the Middle East, Peru, and 19th and early 20th century Russia. Two analyses of religiously motivated violence focus on the Sikhs in India and a messianic Israeli group. The role of cultural narrative in Armenian terrorism also is examined. Finally, ambiguity in the definition and understanding of state-sponsored terrorism is discussed in relation to its implications for threat assessment and counterterrorist policies. Chapter footnotes. For separate chapters, see NCJ 111831-111840.