Abstract: Automated pulmonary function testing apparatus includes a spirometer responsive to the breathing efforts of a patient for producing electrical signals which vary in accordance with volumes of breathed gas and central processing means for calculating one or more pulmonary function parameters associated with such volumes. Display means are adapted to visually display information supplied from the central processing means to an operator and/or a patient under test. In addition, keyboard means coupled to the central processing means are also provided such that upon operation of a particular key, tests may be selected and volumes or other calculated parameters may be visually displayed and/or printed on a permanent record medium.