Stress fractures, were first described in military recruits but in recent years have increasingly been described in runners. In most surveys they comprise between 10 and 20% of all running injuries. The tibia is the most common site of all stress fractures although recent studies involving track and field athletes show an increased incidence of navicular stress fractures. The diagnosis is based on the clinical findings of a history of exercise-related bone pain with local bony tenderness on examination. The diagnosis is often confirmed by a typical appearance on an isotope bone scan or plain radiograph. In general, treatment consists of relative rest from the aggravating activity until symptom-free and then graduated resumption of activity. Attention also needs to be paid to correction of possible causative factors. These include excessive training, low bone density, low calcium intake, menstrual abnormalities in females and biomechanical features such as excessive sub-talar pronation. Certain stress fractures, such as those in the navicular, require specific management, e.g. six weeks non-weight bearing cast immobilization.