Description: The HYDROCOASTAL project aims to enhance our understanding of interactions between the inland water and coastal zone, between the coastal zone and the open ocean, and the small-scale processes that govern these interactions. To achieve these aims, the HYDROCOASTAL project team has developed and implemented new SAR altimeter processing algorithms for the coastal zone and inland waters, and with these processed Sentinel 3A, 3B and Cryosat-2 data to generate an initial 2-year Test Data Set for selected regions. The performance of these new algorithms has been evaluated, by statistical analyses and comparison against in situ data. From this analysis, the best performing algorithms have been identified and implemented in a processing scheme to generate a global scale coastal zone and inland water SAR altimeter data set A series of case studies have assessed these products in terms of their scientific impacts. All the produced data sets will be available on request to external researchers, and full descriptions of the processing algorithms are available via the project web-site. The presentation will provide an overview of the project, and present key results from the coastal zone studies, which have investigated the potential scientific impact and benefits of the new data set in understanding processes in six different coastal regions, including the Severn Estuary in the UK; The German Bight, Southern Baltic and Elbe Estuary; The Venice Lagoon; The Thailand Coast; The Ebro River and Delta, and the Wadden Sea.