A comparative and correlational study was made of 50 juvenile diabetics and 50 individually matched controls. Evaluation included psychiatric interview, psychological testing, interviews in home with parents, and medical rating of diabetic control. For clinical ratings, the diabetics showed significantly more pathology on psychiatric classification, dependence-independence balance, self-percept, manifest and latent anxiety, sexual identification, constriction, hostility, and oral preoccupation. Independently scored test data revealed greater pathological body image, latent anxiety, constraint, dysphoria, and dependency. Adjustment at home and with peers, emotional tone of home, and parental domination-submission behavior and maternal protection-neglect behavior were significantly worse or more extreme for the diabetics. Characteristics significantly related to diabetic control were later onset and shorter duration of diabetes; higher I.Q. and income; later birth order. Psychological characteristics significantly related to good control were normal dependence-independence behavior (nonextreme) and adequate self-percept.