The European Commission conducted through the Marine Science and Technology Programme (MAST-III) and the 5FP Environment programme, various (marine) data management activities, with the objective: To improve coordination, cooperation and exchange of information amongst European scientists; To help the effectiveness of national and international Programmes through better use of research facilities and transfer of expertise and knowledge. These objectives were and still are fully supported by all countries within the European Union through the framework programme of Community Research. To improve coordination, cooperation and the exchange as well as accessibility of information amongst European scientists on the field of the Sedimentology, three projects, EUMARSIN, EUROCORE and EUROSEISMIC, were funded within the framework of MAST-III Supporting Initiatives (Concerted Actions) - EUROCORE and EUMARSIN - and within the 5FP Support for Research Infrastructures/Thematic Networks Marine Research Facilities: EUROCORE A searchable Internet (meta) database of seabed samples from the ocean basins held at European Institutions, Universities and Marine Stations EUMARSIN European Marine Sediment Information Network on the Internet, concerning marine sediment meta-databases of the Geological Surveys of the EU-countries and Norway. EUROSEISMIC European Marine Seismic Metadata and Information Centre. These three projects contributed to the establishment and maintenance of the WWW.EU-SEASED.NET website.