Otoacoustic emissions provide a new method for objective assessment of peripheral auditory function. Emissions have been recorded in 80 patients and comparisons made with subjective hearing tests and brain stem response audiometry. Our experiences confirm that this procedure is rapid and easy to perform, and that the presence of emissions is a reliable indication of normal function in the middle ear and cochlea. This is particularly useful in neonates, young children and adults whose inability to cooperate prevents the use of behavioural audiometry. Recording of otoacoustic emissions can replace brain stem response audiometry as the primary objective assessment of auditory function in these groups.