R. Coletti 1 INTRODUCTION The aim of this paper is to offer an overview on two EU Region-building strategies for Maritime cooperation in the Mediterranean Sea: the European Union Strategy for the Adriatic and Ionian Region (EUSAIR) and the Western Mediterranean Initiative (WestMED). In general terms, regional strategies are based on the definition of transnational areas of cooperation which offer spaces for inter-institutional dialogue between the European Union and third countries on topics of common interest (Coletti & Celata, 2013). As we shall see, these strategies have been largely used by the European Union in the relationship with its neighbouring countries, including in the Mediterranean. In this framework, the peculiar characteristics of both the EUSAIR and the WestMED initiative are to be identified in the wide involvement of stakeholders at different scales that these initiatives ensure, and in the attempt to coordinate and create synergies among different programmes and funds. From this point of view, the EUSAIR and the WestMED initiative may offer a specific added value during the incoming 2021-2027 programming period of EU funds, as they offer a pre-defined and agreed set of priorities where it is possible to focus efforts and resources with the aim of obtaining more relevant and long-lasting results, including in the field of blue growth. The paper is structured as follows: section two introduces policies and practices of EU region-building in the Mediterranean. Sections three and four present the EUSAIR and the WestMED initiative respectively. In section five, the main future opportunities and challenges for the two initiatives are discussed, highlighting the contribution that they may offer to a sustainable management of the Mediterranean Sea. 2 EU DRIVEN REGIONALIZATION PROCESSES IN THE MEDITERRANEAN The EUSAIR and the WestMED initiative, discussed in this brief contribution, are not the first examples of regionalization processes in the Mediterranean; rather the EU has put in place several initiatives of region-building in the area. Firstly, we can say that the very policy frameworks adopted by the EU in the relationship with its neighbouring countries determine different frameworks and regionalization throughout the Mediterranean Sea. With a “territorial turn” adopted in 2007, the European Union has given value to geographical proximity, by adopting the European Neighbourhood Policy for framing the relationships with non-EU countries at EU Eastern border and in the Southern Shore of the Mediterranean. The European Neighbourhood Policy has determined the creation of a geographical category, the “European neighbourhood”, which includes all the recipient countries of the European Neighbourhood Policy despite the profound differences that exist among them (Aliboni, 2005; Dimitrovova, 2010); however, different applications and approaches emerge respectively between the Eastern and Southern dimensions of the Neighbourhood Policy (Coletti & Celata 2013; Celata & Coletti 2015). At the same time, the Enlargement Policy applies to candidate and potential candidate countries in South Eastern Europe, de facto creating a region in the heart of the European Union territory, as evident in Picture 1. 54