The abdominal computed tomograms of 28 patients with a clinical diagnosis of acute small bowel obstruction were reviewed. Computed tomography accurately identified the presence, severity and level of obstruction. Signs such as angulated bowel loops and adjacent streaks within the mesentery at points of luminal calibre change were recognized in 69% of cases with adhesive obstruction. Computed tomography may reveal non-adhesive causes and is the modality of choice for investigating patients with higher grades of bowel obstruction where early surgical intervention is contemplated.