Steven C Hayes and Stefan G HofmannSteven C. Hayes, PhD, is Nevada Foundation Professor in the department of psychology at the University of Nevada, Reno. He has been president of numerous professional organizations, is author of forty-five books and nearly 650 scientific articles, an is among the most cited living psychologists. He has shown in his research how language and thought leads to human suffering, and is originator and codeveloper of acceptance and commitment therapy (ACT): a powerful therapy method that is useful in a wide variety of areas; relational frame theory (RFT): an empirical program in language and cognition; and process-based therapy (with Stefan G. Hofmann).Stefan G. Hofmann, PhD, is professor of psychology in the department of psychological and brain sciences at Boston University. He has been president of numerous professional organizations, and is currently editor in chief of Cognitive Therapy and Research. He has published more than 400 peer-reviewed journal articles and twenty books. He is a highly cited researcher, and has received many awards, including the Humboldt Research Award. His research focuses on the mechanism of treatment change, translating discoveries from neuroscience into clinical applications, emotion regulation, and cultural expressions of psychopathology. He is codeveloper (with Steven C. Hayes) of process-based therapy. Read More Read Less