The overall objective of this preliminary investigation was to determine whether breathing patterns of patients with chronic obstructive pulmonary disease could be altered by training patients to voluntarily change their breathing, using techniques of biofeedback training. The specific aims were (1) to develop a method of monitoring respiratory rate and tidal volume with a device that was both accurate and usable without discomfort or inconvenience to the patient; (2) to use the method with patients having chronic obstructive pulmonary disease to determine whether respiratory rate could be slowed by voluntary controls; and (3) to determine whether patients who could slow their breathing rate would increase their tidal volume and demonstrate other respiratory changes.