Analysis of 84 EEGs recorded during the first 24 hours of life in 80 full-term newborns admitted in intensive care unit for different reasons. - 35 died, 45 survived (normal outcome: 30, minor sequelae: 6, major sequelae: 9). Extremely abnormal EEGs (27 cases) demonstrated singly or in combination: electrical discharges - isoelectric activity (after 10 hours of life) - Permanent discontinuous activity with longest interval greater than 40 seconds, shortest interburst interval greater than 3 seconds, longest burst shorter than 6 seconds. These abnormalities were observed in babies with unfavourable outcome. Normal or minimally abnormal EEGs (31 cases) were observed in babies with normal outcome (21 cases), minor sequelae (3) or in babies died without cerebral injury at autopsy. Twenty-two EEGs could not be classified easily after a single recording, most of then obtained before the 10th hour of life. Sleep state organization was assessed in 56 neonates; sleep state organization was present in 11 infants (normal outcome or minor sequelae). The EEG of the first day of life can be a useful tool in assessing the degree of early cerebral injury in infants requiring intensive care.