MyOcean is a three-year project (2008-2011) which goal is the development and pre-operational validation of the GMES Marine Core Service for ocean monitoring and forecasting. It’s a transition project that will conduct the European “operational oceanography” community towards the operational phase of a GMES European service, which demands more European integration, more operationality, and more service. Observations, model-based data, and added-value products will be generated – and enhanced thanks to dedicated expertise – by the following production units: • Five Thematic Assembly Centers, each of them dealing with a specific set of observation data: Sea Level, Ocean colour, Sea Surface Temperature, Sea Ice & Wind, and In Situ data, • Seven Monitoring and Forecasting Centers to serve the Global Ocean, the Arctic area, the Baltic Sea, the Atlantic North-West shelves area, the Atlantic Iberian-Biscay-Ireland area, the Mediterranean Sea and the Black sea.