The poor results in the treatment of congenital dislocation of the hip stem either from resubluxation after reduction or from the onset of vascular changes in the epiphysis. The former is preventable by treatment. The occurrence of vascular changes in hips reduced after the age of one year, however, at present is neither predictable nor preventable. In the series reported, 35 per cent. showed definite vascular changes and another 20 per cent. had a roentgenographic appearance indicating partial involvement; in seventy-two of the hips involved by such changes adult results were unsatisfactory. Clinically these patients are distinguishable by persistent symptoms at an early age. The changes are considered identical to those of coxa plana manifested at an earlier age. When left untreated, however, they result in more severe adult deformity. A comparably high male sex incidence was noted in both groups of hips. A susceptibility to vascular injury is postulated on the basis of individual variations in the vascular supply to the femoral head. The importance of early recognition for treatment of this disorder cannot be stressed too much. The method of treatment advocated at this time is prohibition of weight-bearing nutil the head appeans healed roentgenographically.