In American criminology, crime and other forms of deviance have often been attributed to individuals’ definitions or internalized attitudes toward deviance. In previous studies, however, empirical tests of the causal processes of learning attitudes toward deviance have been relatively rare. Moreover, studies examining the mediating effect of a person’s attitudes on the relationship of both peer reactions and peer behavior to the person’s deviance are even rarer. These studies also have been largely restricted to adolescent samples from the U.S.