Human impact on runoff and erosion is increasing worldwide because of growing pressure to develop land and water resources. In many parts of the world, however, runoff and erosion rates are not monitored, precluding an accurate assessment of human impact and sustainable practices. The objective of this symposium is to review recent developments in a wide range of methods and techniques that can be used to characterize runoff and erosion in ungauged basins, and to evaluate how to integrate the information obtained using remote sensing, GIS, modelling and other methods into a coherent view of the ungauged basin. This collection of 28 contributions thus provides an up-to-date overview of work worldwide in this field.