Results indicated that approximately one third were functioning in the mentally defective range, one third in the borderline mentally retarded range, and one third in the low average to average range. Almost half showed perceptual deficits correlated with minimal brain dysfunction. Results were highly significant, suggesting that delinquents apprehended and seen in our clinic are likely to be of borderline intelligence or below, showing evidence of minimal brain dysfunction. Hypotheses are discussed, as is the need for appropriate treatment facilities. (Author abstract)