The results of four different types of operation were compared retrospectively in terms of mortality, morbidity, duration of hospital stay. Eighty-eight consecutive patients suffering from left colonic obstruction underwent emergency surgery from December 1976 to January 1988. There were 36 male and 52 female patients, aged from 41 to 93 years (mean 71), 25% of them being 78 or older. Carcinoma was the most frequent lesion (75/88, 85%). 1) One-stage resection and anastomosis was carried out in 23 patients with only one temporary ileostomy; there were two fatalities (8.7%) and one clinical anastomotic leak (4%) treated conservatively with success; mean hospital stay was 21.5 days. 2) Thirty-six patients underwent a Hartmann procedure, with four fatalities (11%) and a mean hospital stay of 23.0 days; 17 of the surviving 32 (53%) later had the second stage procedure, with no fatality, one clinical leak (6%), and mean stay of 20.7 days. 3) Twenty-six patients had simple decompressing colostomies with nine fatalities (35%); eight of the surviving 17 (47%) had colectomy and colostomy closure during the same hospitalization, with one fatality (6%); mean hospital stay was 41.4 days. 4) Finally, subtotal colectomy imposed by caecal ischemia (twice) or a previous right colectomy (in one instance) was performed three times with no death. Since january 1986, resections and primary anastomoses have been performed 20 times for 26 consecutive obstructions (77%). Our overall results in terms of mortality, morbidity and duration of hospital stay appear to favor resection and primary anastomosis in the treatment of selected cases of left colonic obstruction.