This chapter from the Outdoor Emergency Care: A Patroller’s Guide to Medical Care provides a comprehensive overview of heat-related emergencies. It begins by explaining how to prevent these illnesses through preparation and understanding the body's thermoregulation processes in hot environments. The text then details the different types of heat emergencies, including heat syncope, cramps, exhaustion, and stroke, outlining their signs, symptoms, assessment, and management. Finally, it offers a case study to illustrate the practical application of the discussed principles in a real-world scenario.