Mini-perforation of the colon--not all postpolypectomy perforations require laparotomy. In a 10-year experience with 4,784 consecutive colonoscopic polypectomies, the need for operative intervention in just two of seven perforations indicates that patients with specially defined, limited perforations can usually be treated nonoperatively. This specific complication, which has been termed "mini-perforation," is generally detected within 6-24 hours of polypectomy, and is characterized by local pain and tenderness, without signs of diffuse or spreading peritoneal irritation. Free intra-abdominal or retroperitoneal air on x-ray documents the actual perforation. Complete resolution of symptoms within 24-48 hours confirms the diagnosis of "mini-perforation." Success depends on good bowel preparation for colonoscopy, and early recognition of perforation, with institution of bowel rest and intravenous antibiotics. The "mini-perforation" spontaneously closes, probably by omental adherence. Frequent serial clinical examinations are mandatory so that frank perforation with advancing peritonitis will be promptly recognized and treated surgically. An understanding of the three levels of cautery injury to the colon wall--"serosal burn," "mini-perforation," and "frank perforation" are essential in managing the complications of colonoscopic polypectomy. 