The discriminant and concurrent validity of the five new scales for the Devereux Adolescent Behavior Rating Scale (DAB) was explored using a heterogeneous sample of psychiatric and substance abuse patients. Consistent with predictions, the substance abuse patients scored higher on the Acting Out Behaviors (AOB) and Heterosexual Interests (HI) scales, and psychiatric patients scored higher on the Psychotic Behaviors scale. Gender differences also were found, including boys being rated higher on Acting Out Behaviors, and girls higher on Heterosexual Interests. The new DAB scales demonstrated sufficient concurrent validity using a thorough record review and a parent rating scale (the Child Behavior Checklist: [CBCL]). The Neurotic/Dependent Behaviors scale (NDB) showed a consistent relationship with substance abuse and several other measures of more externalizing behaviors, in addition to the predicted relationships with anxious, tense, and dependent behaviors. The Withdrawn/Timid Behaviors scale (WTB) proved to be a purer measure of internalizing behaviors in both sexes.