This article addresses some of the implications of the EU's proposed Marine Strategy Directive for ongoing work in the regional seas conventions and for national work on regional marine strategies. The starting point is the proposed directive's focus on the ecosystem approach to the protection of the marine environment. Key elements within this approach are analysed, such as integration of environmental considerations into other policy areas; introduction of ecological quality objectives; and establishment of holistic monitoring and assessment programmes. Is it possible to transform these concepts into legally binding obligations? What will the implications of the proposed directive be for the rights and obligations of EU Member States under international law? A Management Plan for the Norwegian Part of the Barents Sea (‘Barents Plan’) was adopted by the Norwegian Government in March 2006 and approved by the Norwegian Storting (Parliament) in June 2006. It provides an example of a concrete application of the concepts in the proposed directive. Based on an analysis of the proposed Marine Strategy Directive and the Barents Plan, some key political and legal challenges are discussed in this article.