Spaceborne remote sensing of inland water quality is based on the assumption that the relationship between the reflectance and the concentration of relevant water quality constituents is knowna priori.Simultaneous measurements of the upwelling and downwelling irradiances, along with phytoplankton chlorophyll-a, suspended matter and dissolved organic matter concentration at over 20 water bodies throughout former USSR, Hungary, Germany and Bulgaria, are reported in this article. The measurements cover different trophic states of water bodies, from oligotrophic to hypertrophic, and different climatic conditions. The range of chlorophyll-a is 0·1 to 350 mgm-3, suspended matter is 0·1 to 66mg1-1, and dissolved organic matter absorption at the wavelength 380nm is 0·1 to 12m-1.