Major disasters have been a constant reality since ancient times, repeatedly causing disruption, illness and death. This review presents epidemiological evidence regarding long‐term health effects from a selection of major disasters, which represent some of the more thoroughly studied events in history. The World Trade Center disaster, Bhopal and Seveso chemical releases, Chernobyl nuclear accident and Mount St. Helens and Soufriere Hills volcanic eruptions are discussed in some detail. While this review provides an overview of potential long‐term health outcomes from several types of disasters, it also illustrates the gaps in knowledge that exist for some of these events. There exists a relative lack of research on long‐term health effects for many types of disasters. By illuminating these issues, this review may help to emphasize the importance of focussing efforts and available resources on the study of long‐term health effects related to future disasters.