Ever since the first successful pneumonectomy for lung cancer was performed in 1933, a number of largely historical reports have attempted to look at the physiological consequences of this operation in order to define patient long-term functional status. The pertinence of these contributions is, however, limited because most were performed in patients who had their pneumonectomy for benign diseases or were carried out in small and heterogeneous populations. Thus, several surgical myths and beliefs such as phrenic nerve interruption at the time of operation might be desirable, marked hyperinflation of the residual lung is associated with reduced lung function, and patients develop pulmonary hypertension over time and have poor exercise tolerance have persisted over the years. Our findings based on a study of 100 patients evaluated 5 or more years after surgery (mean follow-up time, 9.1 ± 2.8 years [5.0-14.7 years]) show that most patients can adjust to living with only one lung and are thus able to live a near-normal life. Although diaphragmatic paralysis is characterized by significant alterations in respiratory function, hyperinflation of the residual lung is beneficial.