The question addressed is whether individuals operating at the Postconventional level of moral reasoning behave appreciatively different from those functioning at lower moral maturity levels. The types of behaviors reported in the literature are classified in five areas: resistance to temptation, resistance to social influence/authority, student activism, prosocial behavior, and antisocial behavior. The data suggest that evidence linking Kohlbergian moral development to differential behaviors is remote. However, the link between moral reasoning and behavior is not positively nonexistent. There remain several factors which probably affect the findings in all five behavioral categories, especially the sparsity of subjects at the principled level and the limited range of behaviors investigated.