117 children were examined in Gatien of Clocheville during 13 months. In the same session behavioural audiometry and brainstem auditory evoked response audiometry were performed. With the click technique: BSAER do not identify tonal notchs. The BSAER threshold is higher than the behavioural threshold because low frequencies are not explored in profound deafness. It is difficult to differentiate conductive and perceptive deafness when wawe I is missing. Within these limits BSAER is powerful test in babies and children with behavioural disorders.