The ways in which human activities are altering natural processes of environmental change and the impacts of that change on humans are not evenly distributed across the globe. Because of special combinations of human and natural attributes, some locales are especially prone toward accelerated processes of change induced by human-environmental interactions. This project will begin the establishment of a methodological framework for the systematic, comparative study of human-environmental interactions in five parts of the world where the situation has been assessed as especially critical -- the Mexico Basin, part of the Amazon basin, the North Sea, the Aral Sea, and a part of the Himalayas. Case studies will be undertaken in each of these locales to identify and evaluate the human forces that are altering natural processes of environmental change, the growing societal awareness of these impacts, and the nature of societal responses to those changes. Common research approaches will be used in all case studies to ensure comparability of results. The work will be coordinated by a central research team of scholars with complementary skills and by an international board of advisors, but much of the research will be conducted by scholars based in and familiar with each of study areas. The research also will be coordinated with related activities of study groups of the International Geographic Union. This research will lay the groundwork for an important series of intensive, comparative case studies of human-environmental interaction in five critical parts of the world. The research beginning in this phase of the analysis and likely to continue in future years will provide significant new insights about human and natural processes in the study areas themselves, but more importantly, the research will provide generalizable knowledge about global patterns and processes of human impacts on and responses to natural environmental change. The study will also establish a framework for replication in other locales in order to further increase understandings about this critical topic.