1. A case of arthritis of hip complicating osteitis pubis after retropubic prostatectomy is described.

2. It seems likely that bacterial infection was responsible in this case, although it was not proved.

3. Antibiotics did not appear to influence the course of the disease.

4. The progress of the disease was followed clinically and radiologically to its conclusion by natural healing with absorption of the femoral head, leaving a painless joint with good function.