Previous reports have shown the utility of combined lung and brain surgery in patients with a primary non small cell lung cancer (-NSCLC) and solitary brain metastasis. This paper reports our recent data with the aim to rationalize the indication of this surgical approach. Over a period of eighteen years (1975-1992), 50 patients with NSCLC and solitary brain metastasis underwent combined lung and brain surgery. Fifteen of these patients had a synchronous presentation while the remaining 35 had a metachronous presentation of lung cancer and single brain metastasis. There were no operative deaths and complete remission of neurological symptoms was obtained in 46 patients (92%). Actuarial overall five year survival was 16% with a median survival of 21 months. Age, gender, histology, T status, size and site of NSCLC, site and location of brain metastasis and the association with adjuvant therapy did not significantly affect survival. The variables that were associated with a significantly prolonged survival were type of lung surgery, N status and interval between the two operations. Patients with synchronous presentation had a five-year survival of 6.6%. By contrast the actuarial five-year survival of those patients with the diagnosis of brain metastasis after the removal of NSCLC was 19%. In this subset of patients those with N0 status and a median interval between lung and brain surgery longer than 14.5 months had a significantly longer survival. We may conclude that combined lung and brain surgery is recommended both for relieving neurological symptoms and for prolonging survival. This is particularly true in those patients with limited loco-regional involvement and a late single brain metastasis.