We report the results of a study on psychopathy and its correlates among 203 youths incarcerated in residential commitment programs in Pennsylvania, Ohio, and Delaware. Latent class analysis of the psychopathy data identified three classes of youths: low psychopathy, moderate psychopathy, and high psychopathy. Significant differences were found among the three groups in regard to their criminal thinking, delinquency, experience of stressful events, family relationships, and drug use. Conduct disordered, psychopathic youths were the most troubled among the youths studied. Copyright © 2007 John Wiley & Sons, Ltd.