We present the results of using the Grosse-Kempf interlocking nail in the management of 125 closed and type I open tibial fractures. The mean time to union was 16.7 weeks and no fracture required bone grafting. Mobilisation of the patient and the range of joint movement were better than with other methods of treating tibial fractures. There was a 1.6% incidence of infection; 40.8% of patients had knee pain and 26.4% needed to have the nail removed. Other complaints were minor. We suggest that closed intramedullary nailing with an interlocking nail system is an excellent method of treating closed and type I open tibial fractures.