In recent years numerous publications have appeared in surgical journals, indicating that diverticulitis of the colon is being treated by definitive surgical methods with greater frequency. Although the majority of patients with diverticulitis can be treated by conservative means, estimates have indicated that as many as 25% require surgical therapy. The indications for operation include repeated episodes of acute symptomatic diverticulitis, perforation, obstruction, hemorrhage, possibility of coexistent carcinoma, and fistula formation. Although the incidence of fistula formation has been reported as high as 22.8%,1 this problem has not received analysis proportional to that given the other complications of diverticulitis. Fistulous tracts that result from diverticulitis may extend to the abdominal wall, into the small bowel, and into the bladder. The last site is particularly serious because infection of the urinary tract is a consequence. Consideration of the features and management of this problem led to the present analysis.