During the past months, we have witnessed increasing activity regarding the establishment of a European External Action Service (EEAS) – one of the most emblematic innovations that the Treaty of Lisbon introduces to strengthen the EU external action. While the details of the EEAS organisation and functioning are still under (intense) discussion, this Analysis sheds light on the political and legal contexts in which the EEAS is being set up, and raises some questions as to its possible contribution to the development of a common European diplomacy.