Ukraine's cooperation with NATO is extensive and varied and has become an important expression of the country's Euroatlantic foreign and security policy orientation. This cooperation has expanded steadily since Ukraine became the first CIS country to joint the NATO Partnership for Peace (PfP) Programme in 1994. NATO promotes Ukrainian defence reforms and Ukraine in turn makes a significant contribution to NATO peacekeeping activities. The country is a potential contributor to regional peacekeeping under the EU's European Security and Defence Policy. It could also develop a peacekeeping agenda within the GUAM group of states or within the BLACKSEAFOR naval grouping in the Black Sea region. This paper provides a cogent analysis of these developments which are an important part of the emerging security order in Eastern Europe.