Steven C. Hayes, Ph.D. Steven Hayes is the Developer of Acceptance & Commitment Therapy, the author of the best-selling book Get Out Of Your Mind and Into Your Life featured in Time Magazine. He is a Nevada Foundation Professor at the Department of Psychology at the University of Nevada, the author of 32 books and over 400 scientific articles. Dr. Hayes is the recipient of several national awards including the Lifetime Achievement Award from the Association for Behavioral and Cognitive Therapy.