Master or Servant? The European External Action Service in the EU Common Security and Defence Policy

In December 2009 the Lisbon Treaty provided a new institutional framework for EU foreign and security policy. This article offers an in-depth study of the ramifications of the post-Lisbon institutional dynamics and of their effects on the governance of the EU Common Security and Defence Policy (CSDP), with specific attention being paid to the role of the European External Action Service (EEAS). As demonstrated in relation to the functioning of CSDP, the role of the EEAS, established soon after the coming into force of the 2009 legal provisions, is central in this policy field. Still, a dispersion of decision-making power at the vertical and horizontal level has limited its effective participation in the CSDP decision-making process.