After obtaining hundreds of responses to moral dilemmas, one groundbreaking cognitive-developmental psychologist, Lawrence Kohlberg, proposed that the development of moral reasoning is characterized by a sequence of six stages grouped into three general levels of morality: preconventional, conventional, and postconventional. The table below lists and describes Kohlberg's three levels and six stages of moral reasoning.

Level Age Range Stage Nature of Moral Reasoning
Level I: Preconventional Morality Seen in preschool children, most elementary school students, some junior high school students, and a few high school students Stage 1: Punishment-avoidance and obedience People make decisions based on what is best for themselves, without regard for others' needs or feelings. They obey rules only if established by more powerful individuals; they may disobey if they aren't likely to get caught. "Wrong" behaviors are those that will be punished.
    Stage 2: Exchange of favors People recognize that others also have needs. They may try to satisfy others' needs if their own needs are also met ("you scratch my back, I'll scratch yours"). They continue to define right and wrong primarily in terms of consequences to themselves.
Level II: Conventional Morality Seen in a few older elementary school students, some junior high school students, and many high school students (Stage 4 typically does not appear until the high school years) Stage 3: Good boy/girl People make decisions based on what actions will please others, especially authority figures and other individuals with high status (e.g., teachers, popular peers). They are concerned about maintaining relationships through sharing, trust, and loyalty, and they take other people's perspectives and intentions into account when making decisions.
    Stage 4: Law and order People look to society as a whole for guidelines about right or wrong. They know rules are necessary for keeping society running smoothly and believe it is their "duty" to obey them. However, they perceive rules to be inflexible; they don't necessarily recognize that as society's needs change, rules should change as well.
Level II: Postconventional Morality Rarely seen before college (Stage 6 is extremely rare even in adults) Stage 5: Social contract People recognize that rules represent agreements among many individuals about appropriate behavior. Rules are seen as potentially useful mechanisms that can maintain the general social order and protect individual rights, rather than as absolute dictates that must be obeyed simply because they are "the law." People also recognize the flexibility of rules; rules that no longer serve society's best interests can and should be changed.
    Stage 6: Universal ethical principle Stage 6 is a hypothetical, "ideal" stage that few people ever reach. People in this stage adhere to a few abstract, universal principles (e.g., equality of all people, respect for human dignity, commitment to justice) that transcend specific norms and rules. They answer to a strong inner conscience and willingly disobey laws that violate their own ethical principles.

Sources: Colby & Kohlberg, 1984; Colby et al., 1983; Kohlberg, 1976, 1984, 1986; Reimer, Paolitto, & Hersh, 1983; Snarey, 1995.