THE STUDY SUBJECTS, ALL MALES, HAD BEEN TRANSFERRED TO THE CENTER BY ROUTINE JUVENILE COURT PROCEDURE. THE SAMPLE MAY BE BIASED IN THAT LESS SERIOUS OFFENDERS, WHOSE DISTURBANCES ARE DETECTABLE BY PSYCHOLOGICAL EXAMINATION, ARE NOT SENT TO THE OBSERVATION CENTER. THE SUBJECTS EXHIBITED NO PHYSICAL OR NEUROLOGICAL PATHOLOGY AND HAD NO HISTORY OF ENCEPHALITIS, CONVULSIVE DISORDERS, OR BRAIN TRAUMA. THERE WAS A SIGNIFICANTLY HIGHER INCIDENCE OF EEG ABNORMALITY (62.5 PERCENT) AMONG THE STUDY SUBJECTS THAN IS FOUND IN THE GENERAL POPULATION OF CHILDREN AND JUVENILES. THE INCIDENCE OF ABNORMALITY WAS HIGHEST IN THE 10-12 AGE GROUP (71 PERCENT). ABNORMAL EEG READINGS WERE OF THREE TYPES: (1) DIFFUSE THETA (MATURATIONAL LAG): (2) PAROXYSMAL BILATERAL OUTBURSTS OF SLOW WAVES OF CENTRENCEPHALIC ORIGIN, OR 14-6 CYC/SEC POSITIVE SPIKES: AND (3) LOCALIZED TEMPORAL THETA, PREDOMINANTLY LEFT SIDED. A HIGHLY SIGNIFICANT RELATIONSHIP WAS FOUND BETWEEN EEG ABNORMALITY AND RORSCHACH (INK-BLOT) TEST PERFORMANCE INDICATIVE OF ORGANIC BRAIN SYNDROME. IT SEEMS THAT THE FACTOR OF WEAKENED BRAIN FUNCTIONING SHOULD BE TAKEN INTO ACCOUNT IN THE PREVENTION AND TREATMENT OF DELINQUENCY. DETAILS OF THE EEG ANALYSIS AND A LIST OF REFERENCES ARE INCLUDED.