Influence: The Psychology of Persuasion

The definitive guide to the psychology of why people say yes. Cialdini identifies six principles of persuasion (reciprocity, commitment and consistency, social proof, authority, liking, and scarcity) through a combination of rigorous academic research and undercover fieldwork among sales professionals, fundraisers, and con artists.

Why Start Here

This is Cialdini’s foundational work and the book that established him as the world’s leading authority on influence. Every other book he has written builds on the framework laid out here. The six principles are so well supported by research and so clearly explained that they have become the standard vocabulary for anyone working in marketing, sales, or negotiation.

Understanding these principles serves a dual purpose. You can use them to make your own communication more persuasive, and you can recognize when they are being used on you. Cialdini includes vivid real-world examples of each principle, from how waiters increase tips to how car salespeople manufacture urgency.

What to Expect

A 320-page book that blends academic research with engaging storytelling. Cialdini writes as both a scientist and a storyteller, making dense psychological research accessible and memorable. Each chapter covers one principle with both research findings and practical examples. The revised edition (2006) is widely recommended, though a New and Expanded edition (2021, 592 pages) adds a seventh principle called Unity.