In ten patients with sickle-cell disease, we used a new technique of cement injection for the treatment of 16 painful hips with a radiographic crescent line or flattening of the articular surface due to avascular necrosis. The necrotic bone and overlying cartilage are elevated by the injection to restore the sphericity of the femoral head. Five days after the operation, full weight-bearing was allowed with the help of crutches for three weeks. The time in hospital averaged eight days; the average blood loss was 100 ml. There was early pain relief and postoperative radiographs showed improvement in the shape of the femoral head. At a mean follow-up of 5 years (3 to 7), 14 of the 16 hips were still improved although some gave slight pain. Only two hips had required revision to total hip arthroplasty, at one year and two years respectively. The increasing longevity of patients with sickle-cell disease means that avascular necrosis will be an increasing problem. Total hip replacement has a poor prognosis because of the risks of infection, high blood loss, and early loosening. Cement injection does not have these problems and allows for earlier, more conservative surgery.