Forty-nine Monteggia and forty-seven Galeazzi lesions were treated over a twenty-five-year period. I used Bado's criteria to evaluate the results in the Monteggia lesions. In all of the children in the series either closed or open reduction yielded good results, while the results of treatment of the Monteggia fractures in the adults in the study varied. The best results were obtained in Type-I lesions treated by open anatomical reduction, internal stabilization of the ulnar fracture, and closed reduction of the radial head. Factors leading to poor results in Type-I lesions were failure to obtain anatomical reduction of the ulna, heterotopic ossification including synostosis of the proximal parts of the radius and ulna, and persistence or recurrence of dislocation of the radial head. In patients in whom the radial head could not be reduced by closed methods, the radial head was buttonholed through the joint capsule and the annular ligament was displaced but not ruptured. I have not found that reconstruction of the annular ligament is necessary in the treatment of acute Monteggia fractures. In the Type-II, III, and IV lesions in this series, fair results were the rule. The results of closed reduction of the classic Galeazzi fractures in the adults in this series were not good, due to malunion of the radius and persistent derangement of the distal radio-ulnar joint. The seventeen patients who were treated with accurate reduction and internal fixation of the fractured radius and immobilization of the forearm in full supination for six to eight weeks obtained good results.