One hundred consecutive Social Security applicants with chronic obstructive lung disease were referred for consultative evaluation, including history, physical examination and lung-function tests. There was good agreement between the lung-function tests and the patients' stated ability to climb steps in terms of groups, but in terms of individuals the variation was wide. The response to bronchodilators administered by aerosol spray indicated that some degree of reversibility was present in the majority of subjects. Treatment of these patients did not appear to be optimal. Reasons for this suboptimal treatment include both patient and physician factors. Possible patient factors include poor educational, social, and vocational background, depression, apathy, lack of motivation and possibility of secondary gain. Physician factors include lack of knowledge, limitation in therapeutic skill, and failure to communicate with the patient in a positive fashion. Suggestion for improvement in each possible etiologic factor is made. It is hoped that improvement in care could be translated into rehabilitation of some patients and prevention of disability in others.