The purpose of the BOUSSOLE project is to establish a time series of optical properties in oceanic waters, in support to bio-optics research, to calibration of ocean color satellite observations, and to validation of the products derived from these observations. The bio-optics research as well as the match-up analyses and vicarious calibration experiments are performed based on the data set that is being built from the permanent marine optical buoy and monthly cruises. The site where the mooring is deployed and where the cruises are carried out is located in the Ligurian sea, one of the sub-basins of the Western Mediterranean sea. BOUSSOLE is a joint effort by multiple organizations and is funded and supported by the following agencies and academic or governmental institutes European Space Agency (ESA), Centre National d'Etudes Spatiales (CNES), Centre National de la Recherche Scientifique (CNRS), Institut National des Sciences de l'Univers (INSU), National Aeronautics and Space Administration (NASA), University Pierre et Marie Curie (UPMC), and Observatoire Oceanologique de Villefranche-sur-Mer.