Human diverticular disease was simulated in 21 dogs by intramural injections of a fecal suspension into the wall of the sigmoid colon. After resection of the involved area, the process of wound healing was studied with particular reference to gross and histologic findings, integrity of anastomosis, and collagen concentration. Return to normal colon thickness required 50% more time and the return to comparable rates of collagen synthesis 100% more time in the "diverticulitis" group as contrasted with the control group. The clinical implication of these findings is that great care should be exercised in the staging of resectional procedures for diverticulitis. Based on clinical experience and experimental evidence, more liberal use of the diverting colostomy is advocated in the surgical treatment of this disease.