Spontaneous rupture of the diaphragm is rare. A case is presented in which spontaneous rupture of the left hemidiaphragm occurred as a result of physical exercise 4 months before admission to hospital. The patient, a 42-year-old woman, underwent transabdominal repair with uncomplicated postoperative course. The clinical manifestations, diagnosis and treatment of spontaneous diaphragmatic rupture are reviewed against the background of this case and the total of 12 cases in the available literature. All but one of the ruptures were left-sided. The importance of keeping this condition in mind in differential diagnosis is underlined by the fatal outcome in 2 of the known 13 cases.