- Terror in Ireland: 1916-1923
- Spying on Ireland: British Intelligence and Irish Neutrality during the Second World War
- Book 9781911479574
- Defending Ireland: The Irish State and Its Enemies since 1922
- Intelligence, Statecraft and International Power: Historical Studies Xxv, Papers Read Before the 27th Irish Conference of Historians Held at Trinity College, Dublin 19-21 May 2005








