With the majority of the oceans lying outside the borders of national jurisdiction, it is not easy to preserve them healthy and secure as the ‘shared responsibility’ is not recognized unambiguously in the global world. The recent turn to the maritime sphere is visible in the UN 2030 Agenda on Sustainable Development that has been widely advocated by the EU. The latter’s commitment to sustainable ocean governance involves action beyond borders, which has a considerable impact on the global maritime sphere as well as on developing countries depending on the seas. On the one hand, the EU’s pursuit of sustainable ocean governance is informed by the norms and values that the organization possesses and tries to promote in its response to global challenges. On the other, the normative principles and the EU’s flowery rhetoric serve as a mean to rationalize Union’s pursuit of self-interest. This study analyses both dimensions of the organization’s engagement in the maritime sphere, considering oceans as a ‘placeful’ environment that has to be treated in the same way as the land is. By exploring the external dimension of EU’s action in the field, the thesis allows to see that EU’s pursuit of sustainable ocean governance has to be understood as a process in which the strategic aims are imbued with genuine moral concerns. Nevertheless, those can sometimes be undermined by the material policy outcomes visible in the West African coastal states such as Mauritania and Senegal.