In the instance wherein concentric reduction cannot be achieved by closed method, open reduction is indicated. Prolonged and forceful attempts to reduce the refractory hips are not without risk to the circulation of the femoral head and open reduction is certainly a less traumatic way to obtain reduction in these hips. The authors performed clinical analysis in 30 patients with congenital dislocation of hip who were treated by open reduction between 1978 and 1987, The results are as follows :1. The results of treatment in 30 patients were acceptable in 22(73.3%), uncertain in 4(13. 3%), and unacceptable in 4 patients(13.3%). 2. Comparing the results depending on the presence of prior treatment or not, acceptable results were obtained in 86.4%(19 out of 22) of patients without prior treatment and in only 37.5%(3 out of 8) of patients with prior theatment by such as Pavlik harness and closed reduction. 3. The surgical approaches for open reduction were medial and anterior routes. The approach was selected depending on the age of patients and the severity of dislocation. The medial approach was used in patients under the age of 18 months. In mild degree of dislocation, the age limit of medial approach was extended to 24 months of age. The anterior approach was used in patients over 19 months of age.