CHRONIC obstructive emphysema is a progressive disease which is being recognized and treated with increasing frequency. It is the most common chronic pulmonary disease in the United States. Medical attention for the relief of dyspnea is most often sought by men in late middle age, but symptoms due to emphysema may be severe even earlier in life. Therapy remains challenging and often discouraging, usually falling within the realm of the internist. Selected patients are being referred to thoracic surgeons with much variability in the criteria for selection and little uniformity in the rationale for operation. Consequently, numerous operative approaches to the treatment of emphysema have been used, and an excellent collective review of this subject has recently been published by Knudson and Gaensler.1 Relatively little attention has been paid to defining the morphologic types of emphysema being treated by operation, and correlation with functional data has also been sparse.