We studied dyspnea and pulmonary function during treadmill exercise in 10 patients with pulmonary emphysema before and at least 3 months after thoracoscopic volume reduction. Dyspnea was significantly less after surgery. Ventilatory function, gas exchange, respiratory muscle function, and exercise performance also improved significantly. The degree of volume reduction, estimated by the decrease in FRC as measured by body plethysmography correlated with the degree to which dyspnea was relieved. Volume reduction may be appropriate as a treatment for dyspnea in patients with pulmonary emphysema.