Cecal diverticulitis is a rare entity and remains a difficult diagnostic problem. A retrospective review was undertaken of 16 patients (11 men, 5 women; average age, 33.2 years) with a pathologic diagnosis of cecal or right colon diverticulosis who received treatment from 1979 to the present. Preoperative symptoms were difficult to distinguish from appendicitis. The majority complained of right lower quadrant pain and tenderness. Diagnostic studies were not helpful. Preoperative diagnosis was appendicitis in 88% (14 of 16) and correct in 1 patient (6%). At exploratory celiotomy, the surgeon was able to make the diagnosis of cecal diverticulitis in 9 (60%) of the 15 patients in whom the correct diagnosis had not been made preoperatively. Neoplasm was suspected in 5 patients, and an appendiceal abscess was suspected in 1. Treatment was colectomy in 9 and local excision in 4 patients. In 3 patients, the inflamed diverticulum was left in situ at initial exploration; all underwent later excision, one of these urgently for sepsis. No patient died; however, one anastomotic leak requiring reoperation occurred. On the basis of this experience, we recommend excisional therapy in all cases in which the intraoperative diagnosis is certain. Suspicion of a neoplastic process continues to prompt colectomy in an emergency setting.