Évaluer les impacts des recherches en agriculture sur la société : outils, méthodes, études de cas. Abstract -Evaluation of the impacts of agricultural research on society and ecosystems: tools, methods, case studies. In light of the evolution of issues and development models in the agriculture and food sector, research organizations are questioning the methods to assess the impact of research activities. Indeed, conventional methodological frameworks used since the 1950s are increasingly less adapted to societal expectations and realities of agricultural research. This thematic issue of Cahiers Agricultures "Evaluation of the impacts of agricultural research on society: tools, methods, case studies" presents new methodological approaches developed in recent years by INRA, CIRAD and CGIAR. These methods build on common theoretical underpinnings that emphasize the systemic dimensions of the innovation process, multiple perspectives and longer temporality of impact generation. They also differ in certain dimensions, such as the level of participation of stakeholders in the assessment of impacts. One part of this thematic issue is dedicated to the empirical test of these approaches in developing countries. The issue is enriched by papers providing cross-cutting analyses of the case studies, or presentation of different methods and geographical contexts. Finally, some articles identify the limitations of these methods for future research. This synthesis article presents knowledge on the understanding of the impacts of research activities, and invites readers to reconsider the role of research in the innovation process.