The report describes an impedance pneumograph capable of measuring quantitatively respiratory volumes. Features of this system include the use of a higher frequency (300 KHz) excitation voltage than is normally used in impedance pneumography and the use of pasteless electrodes which are insulated from the subject by a layer of polyethylene, thus forming a capacitive coupling of the electrodes to the subject and eliminating the problems associated with skin-to-electrode impedance changes. A near perfect empiric correlation was found to exist between the transthoracic impedance measured by this device and pulmonary volume.