Behavioral psychology is a branch of psychology that focuses on the study and alteration of people's behaviors, including their actions, emotions and thoughts. Techniques that may be applied include cognitive restructuring, behavioral modeling and, most commonly, classical and operant conditioning. Behavioral psychologists typically work in elementary and secondary schools, businesses, clinics and physicians' offices. They use research-based learning theories to help patients modify their behaviors, and use behavior therapy to treat anxiety disorders, depression, substance abuse, and mental illness. The field is sometimes also known as cognitive-behavioral psychology.