Natural hazards, created when environmental processes such as earthquakes, windstorms, floods, landslides, wildfires, and drought occur in conflict with human populations, continue to take their toll in lives and human suffering. About three million people around the world have been killed in the past two decades, and the lives of about 800 million other people have been adversely affected [U.N. General Assembly, 1987b]. Short-term economic losses have been estimated at $1–$5 billion annually. Single disasters have caused losses in developing countries equal to their annual GNP. Total losses, including damage to health and welfare of human populations from effects of long-term environmental disasters such as desertification and negative effects of global climate change, are accumulating at an alarming rate. Mounting losses of life and property, and economic and political insecurity exacerbated by the effects of disasters, spurred the idea of an organized worldwide effort for a decade devoted to the reduction of natural hazards.