Explaining EU Effectiveness in Multilateral Institutions: The Case of the Arms Trade Treaty Negotiations

Abstract: This article examines the EU's participation in multilateral institutions on the example of the UN Arms Trade Treaty. The central question of the study is to what extent and under what conditions the EU can be seen as an effective actor in multilateral security negotiations. It is argued that overall the EU was an effective player during the multilateral negotiations on the ATT, but the degree of its effectiveness varies along different dimensions. The EU was rather successful in the achievement of its goals and in maintaining external cohesion, but it scored relatively low in its efforts to commit the key stakeholders to sign up to the ATT. The EU's internal export control policy, together with the high level of institutional co-ordination and Member States' interest convergence, facilitated the EU's effectiveness in the ATT negotiations, whereas the international context proved to be the major constraining factor.

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