The spinal evoked potentials on right peroneal nerve stimulation were recorded with surface electrodes in 58 normal children of 41 weeks to 15 years old. Bipolar recordings were performed. In all subjects, tri- or quadri -phasic potentials with poorly defined initial positive phases were recorded. The latency of the evoked potentials increased progressively from the lumbar to cervical location. The peripheral conduction velocity from the stimulating cathode in the popliteal fossa to the lumbar recording location increased until 4 or 5 years, and then reached a plateau. Spinal conduction velocity between the lumbar and cervical locations increased until 7 years, and then remained constant.