This course is an introduction to the topic of natural hazards, their causes and their consequences. The subject is so vast that this course cannot begin to provide a definitive treatment of all aspects of these hazards. Instead, it seeks to present an overview of the general subject. The course begins with a definition of each major natural hazard that disaster managers may encounter in developing countries. Historical examples are presented to give perspective to the potential scope of these natural events and their actual effects within a community or country. The geographical distribution of the hazard type, indicating the possibility of its occurrence in all parts of the world, is shown. The natural pre-conditions that must exist for the phenomenon to occur are described. The actual event is described in its physical/natural manifestation, with a detailed account of what happens and why, before, during, and after the event. The impact on the natural and human-produced environment—the reason it becomes a “disaster” rather than simply a natural phenomenon—is reviewed. Each lesson then discusses what disaster managers, in particular, and the public, in general, can do to respond.