"The GMES downstream project ""AQUAculture USEr driven operational Remote Sensing information services"" (AQUA-USERS) will be a highly user driven project to provide user relevant and timely information to aquaculture industries based amongst others on historic ENVISAT, future Sentinel 3 (and 2) data and innovative optical in-situ measurements. The key purpose of AQUA-USERS is to develop, together with users, an application (app or web based) that brings together satellite information on optical water quality and temperature and (users and partners collected) in-situ observations also on optical water quality, temperature and ecological parameters. Additionally the application will collect relevant weather prediction data and met-ocean data (wind, waves etc) from e.g. MyOcean-2 and models that are run by partners on a routine basis. The application and underlying database and decision support system will link the information to a set of (user determined) possible management decisions. Specific focus during the project will be put on the development of indicators based on EO-data for aquaculture management including indicators for HAB events. We aim at high user uptake and economic sustainability. In 5 countries (Netherlands, Denmark, Norway, UK and Portugal) aquaculture sites will be monitored during 3 intensive case-studies. GMES Satellite products will provide the users (federated in the User Board) with further insights in the characterization of their sites and in the management of operations during adverse conditions."