Objectives: A report from the National Emphysema Treatment Trial indicated that lung volume reduction candidates with a forced expiratory volume in 1 second and a diffusing capacity of carbon monoxide of 20% or less of predicted value were at high risk for mortality and were unlikely to benefit from surgical intervention. This article examines the applicability of the National Emphysema Treatment Trial findings to our own patients. Methods: We reviewed 280 patients who underwent bilateral lung volume reduction surgery at our institution between January 1993 and December 2001. All patients met our selection criteria, including heterogeneous distribution of emphysema. Of these 280 patients, 20 patients had both a preoperative forced expiratory volume in 1 second and a diffusing capacity of carbon monoxide of less than or equal to 20% of the predicted normal values, thus meeting one National Emphysema Treatment Trial criterion for high risk. Outcomes of the 20 patients were assessed through 5 years after the operation. The survival of the 20 patient cohort was compared with that of the 260 patients not meeting the National Emphysema Treatment Trial high-risk criterion. Results: Ninety-day operative mortality included 1 (5%) patient. In all patients the forced expiratory volume in 1 second increased from 0.46 L (17%) to 0.78 L (32%), a 73% change; the diffusing capacity of carbon monoxide increased from 16% to 27%, a 70% improvement; residual volume decreased from 6.33 L (305%) to 4.26 L (205%), a 33% improvement; and room air arterial partial pressure of oxygen increased from 55 mm Hg to 64 mm Hg. Kaplan-Meier 5-year survivals did not differ between the high-risk and non-high-risk groups. Conclusions: Patients with a forced expiratory volume in 1 second and a diffusing capacity of carbon monoxide of 20% or less of predicted value might experience improvements in lung function, exercise tolerance, and quality of life with acceptable morbidity and mortality after lung volume reduction surgery.