The project HERMES is designed to gain new insights into the biodiversity, structure, function and dynamics of ecosystems along Europe's deep-ocean margin to underpin the future development of a comprehensive European Ocean and Seas Integrated Governance Policy. It represents the first major attempt to understand European deep-water ecosystems and their environment in an integrated way (geosphere, hydrosphere, biosphere of a pan-European range). HERMES aims to compare and contrast selected environments around the European margin from high northern latitudes (focus of this IPY proposal) to the Black Sea.