Emergency hemipelvectomy (HP) is a rare procedure. Only three incidents have been previously reported. This paper describes six additional cases, analyzes our results, and sets forth criteria for patient selection. There were five men and one woman. The median age was 38.5 years. Primary underlying diseases were sarcoma (three cases), peripheral vascular disease (one), deep vein thrombosis (one), and drug abuse (one). Life-threatening peripelvic sepsis and hemorrhage were indications for emergency HP. All six patients had multiple procedures prior to definitive HP. Four classical and two modified HPs were performed. The mean operative time was 3.5 hours, the mean blood loss 2292 ml. There were no intraoperative complications. The median duration of hospitalization was 56 days. Five of six patients were saved. Life-threatening peripelvic sepsis or hemorrhage associated with tumor recurrence, radiation, or failed vascular reconstruction is an indication for emergency HP. Neither age nor physical condition should be a deterrent. The patient should not be allowed to advance to a premorbid state before HP is considered, although concomitant intra-abdominal disease is a contraindication. HP is recommended in lieu of hip disarticulation. We anticipate that the need for emergency HP will increase as limb salvage procedures for extremity sarcomas and dysvascular disease become more frequent.