Matthew McKay, PhD, is a professor at the Wright Institute in Berkeley, CA. He has authored and coauthored numerous books, including The Dialectical Behavior Therapy Skills Workbook, Self-Esteem, and Couple Skills, which have sold more than a million copies combined. He received his PhD in clinical psychology from the California School of Professional Psychology, and specializes in the cognitive behavioral treatment of anxiety and depression.
Steven 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, and 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).