Intestinal nonrotation has been recognized as a cause of obstruction in neonates and children and may be complicated by volvulus and intestinal necrosis. It is very rarely seen in the adult and may present acutely as a bowel obstruction and intestinal ischemia associated with midgut or ileocecal volvulus, or chronically as vague intermittent abdominal pain. The purpose of this communication is to reveal the pathogenesis and the surgical significance of intestinal nonrotation in adults and to review the English and German language literature since 1923 to establish the optimal therapeutic management. Between 1983 and 1992, we have managed and observed prospectively 10 adults with intestinal nonrotation. In four patients the nonrotation has been detected at emergency laparotomy owing to midgut or ileocecal volvulus. Four patients suffered from chronic symptoms of intermittent volvulus or small bowel obstruction and in two patients the nonrotation has been noted as an incidental finding at laparotomy for another condition. A survey of the literature from 1923 to 1992 revealed 40 adults with symptomatic intestinal nonrotation to which we contribute nine patients. We establish that in the acute symptomatic pattern, only emergency laparotomy can provide the correct diagnosis and decrease the risk of bowel disturbance. In the chronic situation, barium studies of the upper and lower gastrointestinal tract reveal varying degrees of midgut malrotation and confirm the nonrotation in each case. Also, in these forms the explorative laparotomy with a consequent staging of the abdominal situs is to be recommended. All reported cases at our institutions are without complaints after surgery. Adult patients with intestinal nonrotation and acute or chronic obstructive symptoms or those detected incidentally at laparotomy for other conditions should undergo a Ladd procedure because of the risk of midgut volvulus. In this operation, the nonrotation is left in place and the ascending colon is sutured at the colon descendens and sigmoideum. After this procedure the mesenteric pedicle is fixed and the risk of midgut torsion remains minimal.