This article provides an overview of tsunamis in Japan, including their causes, when they typically occur, which coastal areas are most vulnerable to them and the warning systems and preparedness measures that have been put in place. It also looks at some of the historical tsunamis that have occurred in Japan over the centuries. Tsunami season in Japan usually lasts from May to October and can be particularly dangerous when it coincides with typhoon season. The Japanese Meteorological Agency (JMA) monitors seismic activity throughout Japan and issues warnings when necessary so that people can take appropriate measures to protect themselves from potential danger.