Steven C HayesSteven C. Hayes, PhD, is Foundation Professor in the department of psychology at the University of Nevada, Reno. He is past president of the Association for Behavioral and Cognitive Therapies, and the Association for Contextual Behavioral Science. Stfan G. Hofmann, PhD, is a professor in Boston University's clinical program of the department of psychological and brain sciences, and director of the Psychotherapy and Emotion Research Laboratory (PERL). He is past president of the Association for Behavioral and Cognitive Therapies, and the International Association for Cognitive Psychotherapy. Read More Read Less