Climate hazards such as floods and heat waves are known to affect health. The frequency and intensity of such events may change with global climate change. Our knowledge of the health impacts of such events is now increasing. Heat waves are associated with significant excess mortality, even in the UK population, and this is concentrated in the elderly. Social factors are also important in an individual's risk of dying during a heat wave. Floods may cause long-term psychological consequences. Our current capacity to address the health impacts of such events is, however, limited. There is a need for research to improve the effectiveness of interventions in the near term, as well as assess the adaptation strategies needed to address climate change in the long term.