Constitutional AI is a safety post-training method that guides language models toward helpful, harmless, and honest behavior through an explicit set of principles. It belongs to reinforcement learning from AI feedback (RLAIF), reducing reliance on human preference labels for every example. section 1.20 section 3.8
A simplified process works as follows:
- Create a constitution: a list of principles describing how the model should respond. section 3.8
- Fine-tune one model to apply those principles to scenarios and example outputs. section 3.8
- Have that model critique responses generated by another language model, identify violations, and provide feedback for improvement. section 3.8
Principles and sensitive conversations
Possible principles draw on the Universal Declaration of Human Rights, such as supporting freedom and equality, and Apple’s Terms of Service, such as protecting private information. For self-harm-related prompts, models can critique and label responses without requiring humans to participate in every conversation. section 3.8 section 3.8
Figure 3.2 A simplified version of the architecture in the Constitutional AI method for improving model generations’ compliance with content policies.
A simplified architecture diagram shows how a principle-following model critiques a generator model to improve compliance with content policies. section 3.8

