We studied 21 hips in 20 patients who had acetabular reconstruction with a femoral head allograft in primary (n 2) and secondary (n 19) total hip arthroplasty. The fate of the graft was evaluated by serial bone SPECTs (single photon emission computed tomography). With a mean follow-up period of 37 (30-60) months, 14 of the 21 hips showed evidence of incorporation at earliest 13 (6-18) months after operation. There was no correlation between the fate of allograft and the compatibility of A, B, O blood typing between host and donor, the use of bone cement in the fixation of acetabular component, or loosening of the acetabular component.