A prospective randomized study comparing the results of early with delayed reduction and stabilization of acute femoral fractures in adults was performed over a two-year period in 178 patients. Only patients who were more than sixty-five years old and had a fracture of the hip were excluded. Arterial blood gases, injury-severity score at the time of admission, pulmonary function, days in the hospital, days in the intensive-care unit, and hospital costs were recorded for all patients. The patients were divided into two groups: those who had an isolated fracture of the femur and those who had multiple injuries. When stabilization of the fracture was delayed in the patients who had multiple injuries, the incidence of pulmonary complications (adult respiratory-distress syndrome, fat embolism, and pneumonia) was higher, the hospital stay was longer, and the number of days in the intensive-care unit was increased. The cost of hospital care showed a statistically significant increase for all patients who had delayed treatment of the fracture compared with those who had early stabilization.