Book excerpt: Featuring animal research, from pigeons to primates, this book explains how comparative psychology can enrich our insights into human psychological processes. Each chapter covers a different clinical disorder or problem commonly encountered by clinical psychologists and therapists, including depression, autism and social communication disorders, substance abuse and obesity, and reviews related research into animal behaviors. Revealing how animal models can grant psychologists a better understanding of the motivations and causes for behaviors that are impossible or challenging to study in humans, the authors suggest interventions, drawn from research findings in comparative psychology, that can effectively address psychological disorders in humans.