The disorders of hyperthermia, also known as heat-related injury or illness, exist on a continuum, which is marked by dysregulation of the body’s thermoregulatory capacity. This condition can vary both in presentation and in severity, from benign conditions, including heat cramps and heat edema, to life-threatening hyperthermia, also known as heatstroke. This article will discuss non-life-threatening heat-related illnesses. It is essential to be able to identify and manage these conditions appropriately as moderate hyperthermia can progress to life-threatening heatstroke. As such, including these injuries in medical decision-making, prompt identification, and appropriate treatment is important. This article will also review the epidemiology, including at-risk populations, red-flag features of patient presentations, treatment options and strategies, and preventative techniques, which all play a significant role in decreasing the morbidity, mortality, and healthcare costs associated with these injuries.