The creation of the European External Action Service (EEAS) is one of the most significant changes introduced by the Treaty of Lisbon. Often referred to as the EU’s ‘Diplomatic Service‘, it is aimed at enabling greater coherence and efficiency in EU’s external action. On 1 December 2010 the EEAS started its work. Over the past three years, the EEAS has been variously criticised. Considering the uncertainties about the division of labour and responsibilities, some of the criticism is justified. Albeit, it will require more than a few bureaucratic changes to make the EEAS to speak with one voice. This book attempts not only to focus on the shortcomings concerning the implementation of the EEAS but it also reflects on the added values of the service. For academics and practitioners alike, Dialer, Neisser and Opitz provide a balanced and fine-grained account of the role and functions of the EEAS and invite their readers to further discuss and research on this topic.