ADAPT'EAU aims to contribute to the analysis and management of global change impacts and adaptation patterns in River-Estuarine Environments (REEs), by interpreting the scientific challenges associated with climate change in terms of: (i) scale mismatches; (ii) uncertainty and cognitive biases between social actors; (iii) interdisciplinary dialogue on the ‘adaptation’ concept; (iv) critical insights on adaptive governance and actions; (v) understanding the diversity of professional, social and economic practices vis-à-vis global change. The project aims to build an integrative and interdisciplinary framework involving biophysical and social sciences, as well as stakeholders and civil society partners. The main objective is to identify adaptive strategies able to face the stakes of global change in REEs, on the basis of what we call ‘innovative adaptation options’. We consider the adaptation of Social-Ecological Systems (SES) through the expected variations of the hydrological regimes (floods / low-flow) of the Garonne-Gironde REE—a salient issue in SW France, yet with a high potential for genericity. The ADAPTEAU approach aims to: - Achieve and confront socio-economic and environmental assessments of expected CC impacts on the Garonne-Gironde river-estuarine continuum (task 1); - Identify the emerging ‘innovative adaptation options’ endorsed by various social, economic, political actors of the territory (depolderisation, ‘room for rivers’ strategies, changes in economic activities, agricultural systems or social practices), then test their environmental, economic and social robustness through a selected subset (task 2); - In close cooperation between scientists, managers and stakeholders, build adaptation scenarios and discuss them in pluralistic arenas, in order to evaluate their social and economic feasibility, as well as the most appropriated governance modes (task 3); - Disseminate the adaptation strategies to academics and managers, as well as to the broader society (task 4). The expected results are the definition and the diffusion of new regional-scale reference frameworks for the discussion of adaptation scenarios in REE—and others SESs—, as well as action guidelines to better address climate change stakes.