Although EU member states generally have a comprehensive overview of the groundwater resources in their own homeland and have delineated groundwater bodies for the EU Water Framework Directive, a coherent overview of all fresh groundwater over Europe is not available for policy development and evaluation. The RESOURCE project proposal aims at demonstrating the potentials of the harmonization of information about Europe’s groundwater resources through cross-border demonstrations projects, through harmonized characterization approaches for Karst and Chalk aquifers and through a first information product at Pan-European scale where available data is compiled and integrated to produce a map of the fresh groundwater resources of Europe. The set of deliverables of the RESOURCE project will provide good practices in providing harmonized data and information across borders for assessments of the 3D structure of aquifers, the water volumes available, and the water fluxes and water quality of the resource. Harmonization of such hydrogeological information is a prerequisite for any transboundary groundwater management. A range of regional and national stakeholders will be involved in the work in order to ensure both interaction with authorities that manage and protect groundwater resources and with end-users, thus maximizing dissemination of the results and providing them with easy-access tools through the cooperation with the GeoERA Information Platform Project, jointly prioritizing the information products that are most beneficial for society. The information products to be delivered will serve as a first prototype example of information to be accessible within a Geological Service for Europe.