Europe is a continent with a high coast-to-surface ratio, and European seas encompass a broad range of settings and regimes. The sustainable development of living and non-living marine resources, the protection of the marine environment and the provision of marine-based services are critical to economic prosperity and to the quality of life of European citizens. Addressing these concerns, marine-science researchers conducted a workshop reviewing major topics of European marine research. This publication contains overview and thematic background papers, as well as reports and recommendations for future research covering topics such as ocean-climate coupling, biogeochemistry, coastal and shelf processes, and ecosystem functioning/biodiversity.