Background The burden of heat-related morbidity and mortality will increase as heatwaves become more frequent and intense as a result of global warming and climate disruption. The elderly and those with chronic disease are worst affected. Most heat-vulnerable people are managed in general practice, and so general practitioners (GPs) need to begin planning for how to prevent and manage heat-related morbidity and mortality. Objective The aim of this article is to introduce GPs to heat-related morbidity and mortality, present a model to help guide thinking about prevention of heat-related disease, and provide examples of actions that practices and practitioners can take. Discussion GPs need to be aware of heat stress as a potential cause of morbidity and mortality. Their role crosses the three preventive levels: 1) advocating for mitigating greenhouse gas emissions (primordial); 2) identifying vulnerable people in their practices; and 3) working with these patients and their relatives to incorporate primary and secondary prevention strategies in care planning.