Influence: The Psychology of Persuasion is a book by Robert B. Cialdini that explores the psychology behind why people say “yes” and how to ethically apply these principles in everyday situations. The book has received positive reviews from readers and critics alike, with Barry Ritholtz, chairman, and chief investment officer of Ritholtz Wealth Management, calling it “the foundational and wildly popular go-to resource for influence and persuasion”