OBJECTIVE Completion pneumonectomy (CP) for malignant disease is generally accepted but controversial for lung metastases. The data available show a high perioperative morbidity and mortality with a poor long-term prognosis. We analysed the postoperative outcome and long-term results of our patients undergoing CP. PATIENTS AND METHODS Between January 1986 and May 2003, nine patients underwent completion pneumonectomy for lung metastases. This represents 10% (9/86) of all CPs performed and 1.7% (9/525) of all pneumonectomies. RESULTS One to three metastasectomies in the form of wedge resection (16), segment resection (5) and lobectomies (3) were performed prior to CP. The mean time interval between the operation of the primary tumour and the first metastasectomy was 38 months, the first and second metastasectomy 12 months, the second and third metastasectomy 14 months, and the third metastasectomy and CP 25 months. Six patients had an extended completion pneumonectomy. Operative morbidity and mortality was 0%. One patient is still alive and recurrence-free 9 months after CP. Two patients have recurrent pulmonary contralateral metastases under chemotherapy and six patients died of metastatic disease. Actual survival is 33%, recurrence-free survival (RFS) is 11%. The 3-year survival is 34%. CONCLUSION Since there was no morbidity and mortality in our series, CP for lung metastases seems to be justified but the long-term survival is limited by the occurrence of contralateral or extrapulmonary metastatic disease. Multiple resections of metastases have a positive influence on survival, but the last step of resection in the form of CP does not seem to improve long-term survival.