The authors examined the effects of ethical leadership on follower organizational citizenship behavior (OCB) and deviant behavior. Drawing upon research related to the behavioral plasticity hypothesis, the authors examined a moderating role of follower self-esteem in these relationships. Results from a field study revealed that ethical leadership is positively related to follower OCB and negatively related to deviance. We found that these relationships are moderated by followers' self-esteem, such that the relationships between ethical leadership and OCB as well as between (...) ethical leadership and deviant behavior are weaker when followers' self-esteem is high than low. Implications of these findings for research and practice are discussed. (shrink)