The data for 77 patients with colorectal cancer who underwent emergency surgery for acute intestinal obstruction (57 patients) or perforation (20 patients) within 24 h of admission were evaluated. The patients were older and had more advanced disease than patients undergoing elective surgery for colorectal cancer. Emergency surgery for carcinoma of the right colon consisted of primary resection in 95 per cent of cases and was followed by a 28 per cent mortality rate. Perforated tumours of the left colon and rectum were managed by primary resection in 82 per cent of cases with a 22 per cent mortality rate. In contrast, obstructing tumours of the left colon and rectum were treated by primary resection in 38 per cent of cases with a 6 per cent mortality rate, and by primary decompression in 62 per cent of cases with a 25 per cent mortality rate. The overall postoperative mortality rate was 23 per cent and increased with advanced tumour disease, perforation and peritonitis. Cardiac decompensation and intraabdominal sepsis were the major causes of death. Although the long-term survival rate following emergency surgery was worse than after elective surgery, improvements in outcome should be achieved by better management of the initial emergency situation.