Experimental sutureless colonic anastomosis was evaluated under various conditions during the first 24 postoperative hours. Adaptation of large bowel segments was achieved by interrupted inverting sutures, which were removed after one hour. This short adaptation period was sufficient for fibrinous contact of bowel segments. Breaking strength of intestinal anastomosis was determined under normal conditions, in peritonitis, complete ischemia and unilateral ischemia of one bowel segment. As control parameter breaking strength of conventional anastomosis was determined under normal conditions. We obtained the following results: 1) Sutureless anastomosis exhibited significantly lower breaking strength than conventional anastomosis. 2) Sutureless anastomosis showed a significant increase in breaking strength under normal conditions after the first 6 h, on the contrary breaking strength remained at lower levels in peritonitis. 3) In complete ischemia anastomotic failure was observed even after 3 h of adaptation. Therefore breaking strength was not measurable. 4) Under unilateral ischemia breaking strength of intestinal anastomosis was significantly lower than under normal conditions.