Reconstruction operations for severe acetabular defects using bone grafting and a bipolar hemiarthroplasty retrospectively reviewed in 81 hips between 1983 and 1985. The most common indication was failed total hip arthroplasty. Bone grafts consisted of cancellous bone, bone blocks, and wafer-type grafts used singly or in combination. The follow-up period was 12 to 36 months postoperatively (mean, 16 months). There were 22 perioperative complications (27%) and 13 postoperative complications (16.7%). A majority of hips showed some graft resorption and component migration that worsened with time. There were four graft failures with subluxation of the component, one prosthesis dislocation, and one component disassembly. Ten hips had revision (13.3%) for a variety of reasons. Nevertheless, clinically, most patients (83%) believed the procedure had improved their condition. Reconstruction for severe acetabular defects can be achieved successfully using this technique, but long-term follow-up evaluation is needed to fully assess the role of this procedure in relation to other available options.