Building on complementary skills and perspectives on problems that transcend political borders, we propose to form a new research collaboration between Arizona State University and the Institute of Ecology, National Autonomous University of Mexico (Director, Dr. Dominguez Perez-Tejada) based in the principles and aims of sustainability science. While sustainability science offers no panacea or guarantee of outcome, it does offer a potentially transformative approach to intractable problems based on principles of solutionsoriented research, epistemological pluralism, knowledge co-production and explicit concern with future states. The new research collaboration will be initiated through three activities that will take place in the period of one year, hosted by UNAM: 1) a plenary planning session of 30 scientists from both institutions, resulting in the development of a conceptual framework that will serve as the common basis for the research proposals that will emerge from this collaboration; 2) consultation with key policy actors and decision-makers in Mexico to define the focal problem domains of the collaborative research, and 3) two small-group research proposal preparation sessions. The primary output of these activities will be one or more proposals for submission to NSF, and potentially additional regional funding agencies. Our interdisciplinary research collaboration will focus on two social-ecological systems in Mexico (Mexico City and the Costa Alegre region of the Pacific Coast) that together encapsulate two of the most pressing issues for science today: the future of water in the world's overpopulated urban areas and the viability of economic development and biodiversity conservation in regions of rapid ecological and climatic change and high social inequality.