The context for internal security -- The internal security operation. Evolution of internal security ; Criminalization ; Benefits of intelligence ; Intelligence collection ; Threat assessment ; Special legislation ; Diplock Courts ; "Super-grass" (Informers) ; Republican reaction: hunger strikes ; Political initiatives -- Background of the troubles. British influence and sectarianism ; Irish nationalism and republicanism ; Famine ; Loyalism (Unionism) ; The Orange Order ; Partition ; Discrimination in the North ; Civil rights -- Participants in the struggle. Provisional IRA ; Irish National Liberation Army (INLA) ; Loyalist paramilitaries ; Political parties ; The Republic -- Obstacles to peace. Sectarianism ; Criminalization ; A need for moderation -- Prospects for the future -- Appendix A. Chronology of violence and intimidation -- Appendix B. Major participants in the struggle -- Appendix C. Threat assessment in Scotland Yard -- Appendix D. Statistics on internal security.