Extreme weather events including recently experienced prolonged heatwaves are predicted to increase in frequency and intensity as a result of climate change. Vulnerable groups, and particularly older persons, are at increased risk of heat-related illness and mortality. Multimodal interventions that incorporate community, primary and secondary care programmes are required. Social programmes such as early warning systems, regional heat plans and community-led initiatives that specifically target the isolated, dependent older person are protective. Establishing clear and effective communication on health promotion and preventative measures is the key. Energy-efficient building design and eco-city planning are vital to reduce the impact of heatwaves at both a population and individual level. Anticipatory strategies should be adopted to ensure ample access to fluids, target barriers to increase oral intake and allow early identification of intercurrent illness, along with regular medication reviews. Prompt management of risk factors for the development of heat-related illness and treatment of complications such as heat stroke and cardiovascular events are keys to reducing the negative health impact of extreme heat in at-risk populations. Morbidity and mortality in heatwaves should be preventable. Evidence-based interventions are available to mitigate and prevent the negative health impact of extreme heat and should be implemented in all residential settings.