Assessment of climate change impacts, vulnerability and adaptation requires a combination of generic and context-specific knowledge. Currently, the availability of such knowledge in Europe is fragmented and incomplete. MEDIATION addresses this challenge through six activities: (i) analysis of the decision-making context; (ii) inventory, review and improvement of methods and metrics for impacts and vulnerability analysis; (iii) likewise for costing of impacts and adaptation options; (iv) development of an overarching integrated methodology; (v) development of a flexible, interactive common platform for knowledge sharing; and (vi) dissemination of this knowledge and training. The components of the project will be connected in an iterative fashion, using case studies which combine selected regional, sectoral and cross-sectoral characteristics and policy questions. The consortium combines eleven top European scientific institutions with a high reputation and long experience in impacts, vulnerability and adaptation research and assessment. They represent different regions in Europe with contrasting vulnerabilities, cover the wide array of disciplinary and interdisciplinary knowledge required to assess sectoral and cross-sectoral vulnerabilities, already participate in numerous related European and national research programmes, and have extensive expertise in science-policy interactions. The project will establish an Advisory Group of key international scientific experts and climate change policy makers to strengthen the scientific basis of the project as well as the policy relevance. In addition to scientific innovation, MEDIATION aims at supporting national and international policy development through targeted interactions, including the UNFCCC process (notably the Nairobi Work Programme), and the EU White Paper process, the latter by systematically addressing the components of the 3rd pillar of the EU Green Paper related to knowledge development and sharing.