Four known child somnambulists (nine to eleven years) and four normal children (seven to eleven years) were observed, utilizing all night EEG studies and the REM technique of dream detection. Among the significant observations were: 1, all somnambulistic incidence occurred during NREM sleep, or stages three and four; 2, sleepwalking incidence was shorter and less frequent in the laboratory than at home, and there was amnesia for all events; and 3, bursts of delta frequency were characteristically seen at the beginning of sleepwalking episodes. Bursts of this frequency were also seen during stage three and four of sleep without sleepwalking. This EEG pattern was not seen in the normal children. It is reported by Gibbs to be found in ninety-five percent of normal infants between six and eleven months and to become absent by nine years of age. The authors conclude that both organic and functional factors play a role in somnambulism.