Seventy-three patients with small bowel obstruction due to metastatic carcinoma were seen in the years 1960 to 1979. Twenty-nine patients were seen in the first decade and 44 patients in the second. The most common primary tumor causing metastatic small bowel obstruction was colonic carcinoma, followed by gastric carcinoma. Plain x-ray examinations supplemented by an upper gastrointestinal series with small bowel follow-through were the most useful diagnostic tests. Seventy per cent (51/73) of these patients were initially treated with intravenous fluids and gastrointestinal decompression using a short (32/51) or long (19/51) tube. In eight of 51 patients, nasogastric decompression relieved the obstruction, but in all but one of these patients symptoms and signs of obstruction recurred promptly after tube removal. At laparotomy, the majority of patients underwent either a bypass procedure or resection. The mean survival for the patients bypassed varied from four to seven months; for those that had resection it varied from five to nine months. The mortality rate was high--41 per cent in the first decade and 25 per cent in the second. Of the last 12 patients, eight received hyperalimentation before and after surgery. The operative mortality rate was 12.5 per cent and the mean survival was eight months. It is concluded that: 1) Colonic carcinoma is the most common primary tumor causing metastatic small bowel obstruction. 2) Tube decompression is rarely effective and surgical relief is necessary in the vast majority of cases. 3) Operative mortality has been reduced, partially because of more vigorous support, i.e., hyperalimentation, but the mean duration of survival has not changed significantly.