The value of internal fixation of fractures of the neck of the femur within 6 h was assessed in a review of a 3-year series. Three groups were compared, in which the operation was performed within 6 h, between 6 and 24 h and after 24 h respectively. The time and quality of union and the incidence of collapse of the head of the femur were significantly better in the first group. The difference in the results between the other two groups was not significant. In view of these data the authors recommend the internal fixation of fractures of the neck of the femur within 6 h.