1. Fifty dislocations and fracture-dislocations of the pelvis have been reviewed. 2. Complications were unusual. Two patients with rupture of the bladder died; two with rupture of the urethra survived. Of eight patients with retroperitoneal haemorrhage four died; the treatment advised is controlled blood transfusion maintaining a blood-pressure of not more than 100 mm. 3. Two types of pelvic disruption should be distinguished: 1) pubic injury with sacro-iliac dislocation; 2) pubic injury with fracture near the sacro-iliac joint. The first is twice as common as the second. 4. In each type, displacement is maintained by extension of the hip and outward roll of the limb. This may be controlled by the Watson-Jones plaster method but the pelvic sling technique is preferred and was used in all cases in this series. 5. The prognosis in fracture-dislocations is very good; nearly all patients went back to heavy work. 6. The prognosis in sacro-iliac dislocations is not so good; only half the patients went back to heavy work and there was often persistent sacro-iliac pain. Sacro-iliac arthrodesis is advised in those cases.