The 4th "Oceans fom Space" conference from 26 – 30 April 2010 – organised by the JRC, the European Space Agency (ESA), the US Office of Naval Research, Global (ONRG), the US National Aeronautics and Space Administration (NASA) and the US National Oceanic and Atmospheric Administration (NOAA) – is gathering specialists and experts on remote sensing of the sea to address every facet of satellite oceanography, including missions, satellites, sensors, passive and active techniques, calibration and validation, algorithms and models. The emphasis of the symposium will be on the key information provided by satellites to promote a sustainable use of marine resources and to improve our knowledge of the role played by the oceans in regulating climate.