Bio-optical dataset from Estonian lakes and coastal waters was collected for algorithm development and validation of satellite-derived products. Dataset (https://water.to.ee/) includes 1) radiometric measurement with associated uncertainty estimates; 2) inherent optical properties; and 3) concentrations of chlorophyll a and total suspended sediments. Currently two manuscripts are in progress to publish the results in peer-reviewed journals. Based on this data, Sentinel-2/MSI and Sentinel-3/OLCI radiometric and in-water products were validated over inland and coastal waters and feedback about the performance of the algorithms was given to ESA and EUMETSAT through dedicated Validation Teams. One scientific paper is already published A. Ansper, A.; Alikas, K. Retrieval of Chlorophyll a from Sentinel-2 MSI Data for the European Union Water Framework Directive Reporting Purposes. Remote Sens. 2019, 11, 64. https://www.mdpi.com/2072-4292/11/1/64