Review of cup arthroplasties performed prior to 1970 in sixty hips of fity-one consecutive patients less than twenty years old, with follow-up on fifty-three hips, revealed that fifteen (28%) of the cup arthroplasties were followed by other salvage operations, usually total hip arthroplasty. Of the remaining thirty-eight hips, only twenty-four (63%) were rated satisfactory clinically, although most of the patients considered their cup arthroplasty an improvement over their preoperative status. Patients with bilateral hip disease did very poorly, and results were inconsistent in others. The final range of motion was frequently poor. Results were improved in hips in which acetabular reaming was not required.