This volume is the fifth in a series of publications produced over the last five years on the ecology of tropical savannas. The volumes arise from work undertaken by the Responses of Savannas to Stress and Disturbance (RSSD) Program, under the auspices of the International Union of Biological Sciences (IUBS) Decade of the Tropics Programme, co-sponsored by the UNESCO Man and the Biosphere (MAB) Program. Savannas cover just under one third of the world's land surface and contain a large and rapidly growing proportion of the world's population as well as the majority of its rangelands and livestock. Most savannas are experiencing increasing pressures from demographic and economic changes that have increased dramatically over the past few decades. In addition to the changing patterns in demography and economics, and the forecasts of global warming further alert us to the most important challenge - to conserve and manage wisely the savanna ecosystems of the world. It is this conservation that forms the basis of the work of the RSSD Program. This fifth publication is comprised of research papers presented at the RSSD's international symposium held in Darwin, Australia, in 1988. The papers address the Australian perspective and intercontinental comparisons and come from an international, expert authorship.