Approaches to research on the causes and impacts of soil erosion have changed significantly over recent years. Whereas biophysical research traditionally utilized small, carefully-managed erosion plots, models and methods are now available to study impacts of broad scale management on the hydrology and water quality of catchments and even river basins. Corresponding research tools have been developed for social and economic analysis at the household, farm and community levels. This book reviews the latest developments in such soil erosion studies. These are considered on a matrix of scales, from plot to river basin, and from farm to national policy. Some chapters review background issues while others consider specific methods. Conclusions of working groups are presented in another chapter. The book is based on papers presented at a workshop held in Indonesia in November 1997, and includes authors from Europe, America, Australia and Asia, as well as from several of the CGIAR centers.