From 1970 to 1978, 14 patients with nontraumatic perforations of the small intestine were treated in the Department of General and Abdominal Surgery of the University Frankfurt am Main. In eight cases suture and bypass and/or interval operation with enterostomy was performed. Seven patients survived, one died. In the six other patients resection with primary anastomosis or suture were performed. One patient survived and five patients died following peritonitis due to insufficiency of the anastomosis. The problem of nontraumatic perforation of the small intestine is discussed and the literature reviewed. It is suggested that the operation of choice is suture of the perforation with bypass or the two-stage operation with enterostomy.