Over 250,000 people were killed in the Tangshan, China earthquake of 1976, and other less active tectonic processes can disrupt river channels or have a grave impact on repositories of radioactive wastes. Since tectonic processes can be critical to many human activities, the Geophysics Study Committee Panel on Active Tectonics has presented an evaluation of the current state of knowledge about tectonic events, which include not only earthquakes but volcanic eruptions and similar events. This book addresses three main topics: the tectonic processes and their rates, methods of identifying and evaluating active tectonics, and the effects of active tectonics on society.