The assessment of risks posed by natural hazards such as floods, droughts, earthquakes, tsunamis or cyclones, may not reflect the full range or magnitude of events possible. As human populations grow, especially in hazard-prone areas, methods for accurately assessing natural hazard risks are becoming increasingly important. Jonathan Nott describes the many methods used to reconstruct such hazards from natural long-term records. He demonstrates how long-term records are essential in gaining a realistic understanding of the variability of natural hazards, and how short-term historical records can often misrepresent likely risks.