Games Realising Effective & Affective Transformation (in Societal and cultural domains) Research and innovation in the GREAT project will generate new knowledge of the actual and potential impact of games on European society and new understandings of the innovative uses of games to support the social engagement of citizens. Leveraging the central role of games in contemporary culture, it combines academic studies and practical experimentation with novel applications of games. Using collaborative design and citizen science methods, it brings together researchers with expertise in the areas of games, data analytics, and policy in an integrated investigation, articulated by case studies of the use of games in facilitating dialogue between citizens and policy stakeholders (policy makers, policy implementers, political parties, campaigning organisations and affected citizens). The context for the research is the climate emergency, and each case study is a research cycle addressing a policy issue and research questions, with multiple pilots and quantitative and qualitative research activities. An important aspect of the method is to place games in an authentic context, so that players are aware that their activities have real-world implications, and to close the loop by including interactions with policy stakeholders. Agile methods are applied to adapt games from existing platforms, for use as research tools: (a) short games deployed at scale in hit mobile games, generating quantitative data and reaching 3 million players, and (b) longer collaborative games based around social dilemmas with small groups, generating in-depth qualitative data. Research outcomes include publication of research findings in journal papers, a method for using games to rapidly obtain data and insight for policy stakeholders, technical resources and guidance for adoption, and implementation of the method.