We reviewed a series of fifty patients who had a non-union of a fracture of the clavicle. Twenty-one patients (42 per cent) who had a symptomatic non-union of the middle of the shaft of the clavicle were treated with open reduction, internal fixation with a modified Hagie intramedullary pin, and autogenous bone-grafting, and those patients form the basis for the report. The average duration of follow-up was thirty-five months (range, five months to eleven years). Healing occurred in twenty (95 per cent) of the twenty-one patients. Intramedullary fixation has several advantages compared with other treatments, such as fixation with a plate and screws. It can be performed through a cosmetically acceptable incision in the Langer line; less dissection of the soft tissues is needed; and, after healing, the pin can be removed through a small incision under local anesthesia.