Diverticulitis is the commonest cause of a sigmoidovesical fistula. Another inflammatory process, neoplasia, trauma, or a congenital abnormality may be responsible. A highly resistant lower urinary tract infection should suggest the possibility of an incipient or established vesico intestinal fistula. Pneumaturia and fecaluria are positive evidence of such a communication. Surgical excision of the diseased segment of colon and closure of the vesical opening is the procedure of choice. In many cases this may be carried out as a primary procedure. General Background History. —Cripps,3in 1888, found that inflammatory lesions more frequently caused sigmoidovesical fistula than did malignant lesions. Heine,5in 1904, and Moynihan,11in 1907, realized the importance of diverticulitis as an etiologic factor in these fistulae. In 1917, Telling and Gruner15made an extensive study of diverticulosis and diverticulitis and observed that in 19.8% of the cases reviewed some type of fistula was