This is a monograph on the subject of sacro-iliac tuberculosis. The author discusses the literature, etiology, pathology, diagnosis, prognosis, the roentgen examination and treatment. He divides the treatment into nonoperative and operative. Under nonoperative is included immobilization combined with horizontal and vertical extension. He discusses operative treatment under osteosynthesis and gives the operative technic for extra-articular arthrodesis. He gives descriptions of various methods of resection and states the indications for operations and the contraindications. He gives his results in thirty-eight cases. The roentgenograms are not instructive because it is difficult to reproduce pathologic changes in this joint. His diagrams are instructive. He discusses the methods of Smith Petersen and Rogers, Picque and Verrall. The book will interest those concerned with sacro-iliac tuberculosis.