Awakening was studied in 15 newborn babies using polygraphic recording to monitor the EEG, eye movements, the EMG activity of muscles of the face (frontal, periorbital and jaw) and to study the respiratory and cardiac rhythms. Twenty arousals, characterized by crying or by eye opening, lasting 2 min were isolated. The two sorts of awakening could be observed in the same child. The study of different parameters during the minutes which precede waking shows that this always happens in agitated sleep, either in a phase of muscular relaxation (9 times), or in a phase of agitation (11 times) characterized by the presence of a phasic EMG activity in the face muscles and brusque movements of the head, the limbs and the body, without tonic activity. This isolated phasic muscle activity, however, was typical of agitated sleep and did not constitute a sign of pre-awakening. Awakening was unpredictable, characterized essentially by a prolonged opening of the eyes, crying, and by the return to tonic muscular activity associated with phasic activity. No relation was observed between the mode of awakening and the type of agitated sleep which preceded.