Compliance refers to the adherence to, or acceptance of, a request. There may be a number of ways to organise the compliance literature, although this article will focus on the categorisations proposed by Robert Cialdini. Specifically, this entry will explore the following principles: reciprocity, consistency and commitment, social proof, liking, authority, and scarcity. Each of these principles has been explored in real-world settings and together they form the foundation of the compliance literature. This article discusses real-world examples for each principle, notes some competing theories, and explores resisting compliance through the awareness of these principles.