WISER will support the implementation of the Water Framework DirectiveDirective 2000/60/EC to establish a framework for water policy and management in Europe (WFD) by developing tools for the integrated assessment of the ecological status of European surface waters. The project will analyse existing data from more than 90 databases compiled in previous and ongoing projects, covering all water categories, organism groups and environmental stressor types. Field-sampling campaigns will supplement the data on lakes and coastal systems. The data will be used to test and complement existing assessment schemes with a focus on uncertaintyMeasure of confidence to express the degree to which a result is subject to chance affects on classification strength. Biological recovery processes after release from hydromorphological and eutrophicationEnhanced primary productivity caused by nitrogen and phosphorous pressures will be analysed. Therefore, large-scale data will help to identify linkages between pressure variables and organism’s responses. Selected case studies, using a variety of modelling techniques, will address pressure-response relationships and evaluate the efficacy of restorationActivity to improve the status of degraded waters, be it waste water treatment or structural improvements. WISER will provide guidance for the next steps of the intercalibration exercise by comparing different intercalibration approaches.