In order to examine the relationship of dyspnea to anxiety and depression, the authors rated dyspnea using several methods in 50 patients with chronic respiratory impairment. Anxiety and depression were measured by the Symptom Checklist-90 and the Symptom Questionnaire. Results varied with the method of assessing dyspnea. Physician-rated dyspnea was significantly associated with patients' self-ratings of breathlessness as well as with pulmonary function tests, but not with any of the self-rating scales of emotions. Self-rated breathlessness was significantly associated with self-rated depression. In multiple regression analyses, depression was predictive of breathlessness. When the sample was limited to patients with chronic obstructive pulmonary disease, the results remained the same. The patients were significantly more depressed and anxious than matched family practice patients. In the study of the complex relationship of dyspnea to physical and emotional factors, it is desirable to use more than one measure of dyspnea because the results depend in part on the method of assessment.