"Choice Theory: A New Psychology of Personal Freedom" is a book by William Glasser that presents a framework for understanding human behavior. It emphasizes that individuals have the power to make choices that influence their lives, focusing on the importance of personal responsibility and internal motivation rather than external factors. The theory posits that all behavior is driven by the desire to satisfy five basic needs: survival, love and belonging, power, freedom, and fun. By recognizing these needs, individuals can make more informed choices that lead to greater personal fulfillment and improved relationships.