The circular stapler was used for colorectal anastomosis in 38 patients (rectal carcinoma 37 cases, sigmoid diverticulitis one case). In Singapore Chinese patients, the most commonly used cartridge size was the EEA 28 mm and ILS 29 mm. The incidence of clinical anastomotic leakage in patients with complete resection rings was 10% (three leaks in 32 patients), leakage occurring only amongst the 24 patients who had resection of a tumour 6-9 cm from the anal verge. Significant, though easily dilatable, stenosis occurred in three patients (8%), and was associated with rectal membrane formation in two patients. Local recurrence, occurring in seven patients in a 0.5-3 year follow-up period was associated with Dukes' C disease; two recurrences occurred in four patients in whom the distal bowel clearance was less than 1.5 cm. The circular stapler facilitates sphincter conservation in mid-rectal cancer and its use in low anterior resection is justifiable when performed with a distal bowel clearance of 2 cm and complete excision of pararectal tissue above the pelvic floor muscles.