The authors have reviewed the clinical and radiological results of 70 intertrochanteric osteotomies in 65 patients. The mean follow-up was 8 years and most of the patients (53 osteotomies) were examined from 6 to 15 years after operation. The mean age at operation was 47 years. In almost two-thirds of patients the osteoarthritis was secondary to congenital disorders of the hip. The technique was usually a rotational osteotomy with slight medial displacement. The clinical results were satisfactory in 49 osteotomies and unsatisfactory in 21. The radiological results were less encouraging, but an impression was gained that a poor radiological appearance does not necessarily preclude a good clinical outcome. There was no significant statistical difference in the results between primary and secondary osteoarthritis. No clear patterns could be established to explain why the operation succeeded in some patients and failed in others.