ERPL/REDP, vol. 18, no 2, summer/été 2006 THE DYNAMIC NATURE OF THE ACQUIS COMMUNAUTAIRE IN EUROPEAN UNION EXTERNAL RELATIONS * ROMAN PETROV ** 1. INTRODUCTION RECENT years have seen profound and wide-ranging changes to the nature and structure of the European Union (EU). The signing of the EU Constitutional Treaty has paved the way for European nations to realise the approaching of the ambitious aim of the Maastricht Treaty, that is to create an ‘ever closer union among the peoples of Europe’, based on the values and principles shared by all Member States. This has been achieved through the identification of the Union as the incarnation of democratic values and principles which are respected worldwide. Throughout the history of European integration, the notion “acquis communautaire” has remained one of the least-well defined, and one of the most-frequently applied. Having been conceived as a concept linked to the EU legal order, the acquis communautaire has quickly become associated with the wider domains of EU policies. In particular, the EU has actively used the “acquis communautaire” to strengthen the integrity of its internal legal and political order and to serve its far-reaching external policy ambitions. Our article focuses on two major objectives. The first is to shed some light on the dynamic character of the acquis communautaire. The second is to study the phenomenon of the acquis communautaire as an instrument of the EU external policy. In the first part of the article we shall argue that the acquis communautaire mirrors the dynamic character of the EU legal * This article is based on the author’s doctoral thesis Exporting the acquis communautaire through EU external agreements which was awarded a special distinction by the Thesis Prize Committee 2005 of the European Group of Public Law. ** Jean Monnet Module Lecturer in EU law at the Donetsk National University (Ukraine). Max Weber Fellow at the European University Institute in Florence