Believed there are 3 stages: pre-conventional, conventional and post-conventional
Each stage had 2 subsections
Pre-conventional stage subsections

Avoid punishment
Seek rewards
Conventional stage subsections

Good boy behaviour (please others)
Law and order
Post-conventional stage subsections

Social contract
Universal principles
Kohlberg's research
1. Studied 75American boys aged 10-16 for 12 years
2. Compared to boys from other cultures like Turkey and Mexico
3. Asked hypothetical moral dilemmas and recorded answers/justifications
4. Example: Heinz Dilemma
Kohlberg found that participants progressed through the stages in a linear order as they aged, but not all reached the final stage
When children were given the views of children in a stage above them, they tended to move up to this stage
Middle class boys were more advanced in moral judgement
Kohlberg concluded that his theory was correct and not influenced by social, cultural, or religious differences
The stages are ordered hierarchically, with higher-order stages being more complex than lower ones.
Higher levels of morality involve greater concern for others and society as a whole.
Children's understanding of right and wrong is based on their own needs and desires at first, then gradually becomes more concerned with other people's feelings and expectations.
At the highest level of development, individuals strive to maintain consistency between personal values and principles and those of society as a whole.