Twenty-five consecutive nonunions or delayed unions of the femoral shaft were treated by a fluted intramedullary rod. Fourteen patients were men; 11 were women. Sixteen fractures represented failures of closed management. Five patients had failures of primary open reduction and internal fixation. Four patients had had one attempt at operative treatment of nonunion. All but one fracture united. The one exception required a second procedure. Excellent bending and rotary fixation were achieved and union occurred promptly in most cases. Iliac crest bone grafting was not routinely required for good results. There were no major complications in this series. Two patients with severe knee extension contractures required quadricepsplasty at a later date to recover knee motion. One fracture healed with a 15 degree valgus malunion. The strength and rigidity make this device extremely reliable for the treatment of femoral shaft nonunion.