The project IMPACT-SC5 aims to assess the impacts of the 87 funded RIAs and IAs, through a multilevel analysis, starting at project (participant) level, via portfolio, network and context analyses. It applies a rigorous methodology that enables to capture the various (intended and unintended) impacts of projects and groups of projects. Horizon 2020 contributes, via its focus on ‘Societal Challenges’ (SCs), to the ongoing paradigm change in Research and Innovation Policy. The pursued objectives are not only to generate economic growth and jobs, but to help resolve pressing socio-economic challenges, including those related to climate, environment, resource efficiency, and raw materials (SC5). The challenge orientation of H2020 implies monitoring the progress of the projects towards the achievement of the targeted objectives and impacts. The scientific, economic and societal/environmental performance of the 87 RIA and IA projects under the SC5 Work Programme 2014-15 will be measured by means of an extensive set of indicators. A portfolio analysis will complement the project-level analysis in order to determine how projects perform together in relation to different objectives. IMPACT-SC5 explores impact pathways to identify good practices and draw recommendations for policymakers and potential EU research funding beneficiaries to increase the impacts of future SC5 projects. Particular attention is paid to the broad and changing policy contexts to ensure a holistic approach for a better understanding of the performance (and the underlying factors) of the 87 projects. Throughout the project, stakeholder engagement will be strongly fostered. The methodology and findings (including the recommendation) will be validated with high-level experts and practitioners who will also be channels for dissemination. The methodology will be made available to the European Commission for its use in the ex-post evaluation of H2020 or future evaluation exercises.