Terrorism and Global Disorder: political violence in the contemporary world, published by IBTauris in 2006

Rethinking the Rise and Fall of Apartheid: South Africa and World Politics, published by Palgrave Macmillan in 2005.

Democracy and Ethnic Conflict: Advancing Peace in Deeply Divided Societies (Palgrave Macmillan 2004)

(editor); A Farewell to Arms?: beyond the Good Friday Agreement (second edition: Manchester University Press, 2006)

(jointly edited with Michael Cox and Fiona Stephen); South Africa in Transition: The Misunderstood Miracle (IBTauris, 1999);

The Age of Terrorism and the International Political System (IBTauris, 1995),

Northern Ireland: The International Perspective (Gill and Macmillan, 1988);

(with John Brewer, Ian Hume, Edward Moxon-Browne and Rick Wilford) The Police, Public Order and the State (Macmillan, 2nd edition 1996),

(editor) New Perspectives on the Northern Ireland Conflict (Avebury, 1994).