1. ‘A’ Department 1
  2. ABC Trial 1
  3. Abdoolcader, Siroj Hussein 1
  4. Abu Nidal 1, 2
  5. Adams, Dominic 1, 2
  6. Adams, Gerry 1, 2
  7. Agee, Philip 1
  8. al-Megrahi, Abdelbaset 1
  9. Aldermaston marches 1, 2
  10. Aldershot Barracks bomb (1972) 1
  11. Aldridge, Philip 1
  12. Alexander II, Czar 1, 2
  13. Ali, Tariq 1
  14. All Russian Co-operative Society (ARCOS) 1, 2, 3, 4
  15. Allason, Rupert 1, 2
  16. Allen, Percy Sidney 1
  17. Allison, George 1, 2
  18. American Civil War 1
  19. An Garda Síochána 1, 2, 3, 4, 5, 6, 7
  20. An tÓglách (Irish republican paper) 1
  21. anarchists 1, 2
  22. Anderson, John 1
  23. Anderson, Robert 1, 2, 3, 4, 5, 6
  24. Andrew, Christopher 1, 2, 3, 4, 5, 6, 7, 8
  25. Andropov, Yuri 1
  26. Anglo-German Fellowship 1
  27. Anglo-Irish Treaty 1, 2
  28. Anglo-Irish War 1
  29. Angry Brigade 1
  30. Annesley, Hugh 1
  31. Anti-Apartheid Movement (AAM) 1, 2
  32. Anti-Terrorist Branch 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16
  33. Arab–Israeli conflict 1
  34. Argov, Shlomo 1
  35. Arnot, Robin Page 1
  36. Aubrey, Crispin 1, 2
  37. Autonomie Club 1, 2, 3
  39. Auxiliary Police Service (Ireland) 1