&NA;The traditional work‐up of patients with lower left quadrant peritonitis often includes the eventual use of barium‐enema radiography. Diagnosis is usually delayed until adequate patient stabilization allows diagnostic contrast enemas. Delay of accurate diagnosis may, at times, have serious clinical sequelae. The use of barium enema in acute lower left quadrant peritonitis has both theoretic and actual disadvantages. These include extravasation of barium, with resultant barium cellulitis and peritonitis, precipitation of acute obstruction, and delay in evaluation by endoscopy, sonography, computerized tomography, and angiography. Forty recent cases of lower left quadrant peritonitis were evaluated on admission by water‐soluble contrast enema. Watersoluble contrast enemas appear to be safe and accurate and avoid the aforementioned disadvantages of barium.