&NA;Between 1978 and 1990, 23 patients underwent 35 thoracotomies for metastatic colorectal cancer. The pulmonary disease was diagnosed within an interval of 0 to 105 (average, 33.4) months after colon resection. Fifteen patients underwent a single thoracotomy; 12 patients had solitary lesions, and three patients had multiple nodules. Eight patients underwent multiple thoracotomies. The median survival following thoracotomy was 28 months; three‐year survival was 45 percent, and five‐year survival was 16 percent. Factors that had no significant bearing on survival included origin and stage of the primary tumor and patient age and sex. An interval before thoracotomy of three years had an impact on survival approaching statistical significance(P=0.17). Patients who underwent multiple thoracotomies had a significantly prolonged survival(P=0.04). Patients who underwent a single thoracotomy for a solitary lesion had a significantly prolonged survival compared with patients who had a single thoracotomy for multiple metastases. After thoracotomy, 14 patients eventually developed recurrent disease, which was confined to the lung in only four patients. Of these 14 patients, 11 subsequently died of cancer. We conclude that thoracotomy for metastatic disease should be considered when the primary tumor is controlled, the lungs are the only site of metastatic disease, and there is adequate lung reserve to withstand surgery. Survival following thoracotomy may be influenced by the interval before diagnosis, the number of pulmonary nodules, and the number of thoracotomies performed.