Although there has been considerable research on attachment and delinquency, few studies have focused on gender differences. This study used a survey of adolescent boys and girls incarcerated in the Wyoming Boys' and Girls' Schools to examine (a) differences in boys' and girls' level of attachment to parents, peers, and school; and (b) the effects of the various attachments on the severity of boys' and girls' self-reported delinquency. The results show no differences in boys' and girls' levels of attachment. However, gender differences in the effects of the various attachments on severity of delinquency were found. Attachment to parents reduced the severity of boys' delinquency, whereas attachment to peers and school reduced the severity of girls' delinquency.