Closed Ender nailing was used in sixty fractures of the femoral shaft. Follow-up examination in fifty-two cases is reported. There were only two failures of the method, both in fractures with supracondylar extension. Simple transverse and short oblique fractures and those with unicortical comminution were shown to be stable after nailing, while long oblique fractures and lesions with bicortical comminution had a tendency to shorten and often required cerclage wiring, cast-bracing, or traction. The average hospital stay was 23.7 days. The operations were simple and quick. There was one case of osteomyelitis, one of clinically apparent thrombophlebitis, and one of fat-embolism syndrome in a patient with multiple fractures and multisystem injuries. There were no cases of breakage of the nail, delayed union, or non-union. In most cases knee motion returned to the preinjury level, although in five knees removal of the nails was necessary. The two failures of nailing which required plate fixation occurred in fractures extending into the supracondylar region. Therefore, these fractures are not suitable for Ender nailing.