So far, the Geological Surveys of certain European countries, like Sweden, Norway, Denmark, Finland and Greece, in which REE deposits occur, have carried out an important work on defining and characterizing their domestic REE resources. In addition, significant initiatives have been taken towards the establishment of a collaborative REE research network in the Nordic countries, supported by a strong EU political backing. Such separate efforts resulted in the detailed mapping and documentation of national or in some cases of trans-national REE deposits. Concerning the documentation of all the potential (known and predicted) REE mineral resources within the EU, a first effort has been made in the FP7 project ProMine (http://promine.gtk.fi/ – coordinated by GTK), which includes the REE resources in the developed pan-European GIS-based database of the EU strategic reserves (including secondary resources). However, all these efforts do not correlate the European REE ore deposits in a way to support the development of know-how for their exploitation. In EURARE project, the data existing for the European REE resources will be assessed and improved in a system, which (i) will include the knowledge, already gained around Europe, (ii) will provide new knowledge for the exploitable REE mineral resources within Europe (including secondary ones) and (iii) will build-up knowhow for their sustainable exploitation. The resulting “Integrated Knowledge Management System for European REE Resources” will be based on high-level standards and specification, like EarthResourceML and GeoSciML, in order to ensure homogenization of data entry and a common format for data sharing. Except for reporting the characteristics of the REE deposits, the developed Integrated Knowledge Management System will include data on estimating the economic value of REE deposits as reserves (proven) or resources (inferred), will provide valuable information on methods and technologies applicable for their sustainable exploitation and will interlink REE metal values and end-products with the demand of European downstream industries. In order for the developed system to be more effective and operational, data entering will follow an INSPIRE  compliant way, achieving a Pan-European dimension for the provided knowledge and know-how. (Cooperation Work Programme FP7 NMP.2012.4.1-1 Collaborative project/ Integrating Project EURARE page 4 of 10). The Geological Surveys from the 6 European countries participating in EURARE, which are already involved in national and joint projects for the documentation of exploitable REE deposits, will become the main drivers for the development of this system and will collaborate with other Geological Surveys around Europe, to achieve the pan-European dimension of the system. This work is of fundamental importance for the European REE extractive, processing and downstream industry, ensuring direct economic benefits, as it will define the exploitable European REE mineral resources and provide sustainable methods and technologies for the extraction of valuable raw materials needed in the European REE downstream industries. After its completion, the Integrated Knowledge Management System for European REE Resources will represent a European Inventory that will act as a roadmap, contributing to related policies and initiatives of raw materials at Europe and drawing a European strategy for the critical metals’ research and exploitation that will cover the whole added-value chain.