In the past decade over ten major tsunami events have impacted on the world's coastlines, causing devastation and loss of life. Evidence for past great tsunami, or 'mega-tsunami', has also recently been discovered along apparently aseismic and protected coastlines. With a large proportion of the world's population living on the coastline, the threat from tsunami can not be ignored. This book comprehensively describes the nature and process of tsunami, outlines field evidence for detecting the presence of past events, and describes particular events linked to earthquakes, volcanoes, submarine landslides and meteorite impacts. While technical aspects are covered, much of the text can be read by anyone with a high school education. The book will appeal to students and researchers in geomorphology, earth and environmental science, and emergency planning, and will also be attractive for the general public interested in natural hazards and new developments in science.