(with James Sperling), 'NATO's Intervention in the Afghan Civil War', Civil Wars, Vol.14(3), 2012, pp.344-372.
'NATO since 9/11' in R.E. Utley (ed), 9/11 Ten Years After: Perspectives and Problems (Aldershot: Ashgate, 2012)
'NATO's Post-Cold War Operations in Europe', in J. Sperling and S.V. Papacosma (eds), NATO after Sixty Years: A Stable Crisis (Kent, Ohio: Kent State University Press, 2012)
(co-authored with J. Sperling and M.A. Smith), NATO's Post-Cold War Trajectory: Decline or Regeneration? (Houndmills, Basingstoke: Palgrave Macmillan, 2012)
Three Questions for the Strategic Concept’, in J. Ringsmose and S. Rynning (eds.), NATO’s New Strategic Concept: A Comprehensive Assessment (Copenhagen: Danish Institute for International Studies, 2011).
'The Common Security and Defence Policy in a Multilateral World', in P. Koutrakos (ed), European Foreign Policy: Legal and Political Perspectives (Cheltenham: Edward Elgar, 2011).
(co-authored with Lorenzo Cladi), ‘Italian Foreign Policy in the Post-Cold war Period: A Neoclassical Realist Approach’, European Security, Vol.20(2), 2011
‘NATO: within and Between European International Society’ Journal of European Integration, Vol. 32(2), 2011 (special issue co-edited by Yannis Stivachtis and Mark Webber on ‘Europe after Enlargement’)
(co-authored with James Sperling), ‘NATO: from Kosovo to Kabul’, International Affairs, Vol.85(3), 2009.
‘NATO: The United States, Transformation and the War in Afghanistan’, British Journal of Politics and International Relations, Vol.11(1), 2009
(with M.E. Smith), 'Political Dialogue and Security in the European Neighbourhood: The Virtues and Limits of “New Partnership Perspectives”’, European Foreign Affairs Review, Vol.13(1), 2008
Inclusion, Exclusion and the Governance of European Security (Manchester and New York: Manchester University Press, 2007).
(as lead author with T. Terriff, J. Howorth, S. Croft and E. Krahmann), 'The Governance of European Security', Review of International Studies, Vol.30(1), 2004
(as lead author with M. Smith and others), Foreign Policy in a Transformed World (Harlow, Essex: Prentice Hall/Pearson Education, 2002)
(as editor and contributor), Russia and Europe: Cooperation or Conflict? (Houndmills, Basingstoke: Macmillan Press, 2000)
CIS Integration Trends: Russia and the Former Soviet South (Royal Institute of International Affairs, Former Soviet South Key Paper, 1997)
The International Politics of Russia and the Successor States (Manchester and New York: Manchester University Press, 1996)