The European Directory of the Ocean Observing Systems (EDIOS) is an information system for marine observing and monitoring programmes, stations and platforms (including moored buoys, coastal installations, seabed stations, drifting buoys, repeated sections and sampling stations, airborne repeated tracks, etc) where there are routine, repeated, and consistent long-term observations of the marine environmental conditions, and where the data are made available for use in real-time, or near real-time. This directory includes discovery information on location, measured parameters, data availability, responsible institutes and links to data-holding agencies.