Matthew McKay, PhD, is a professor at the Wright Institute in Berkeley, CA. He has authored and coauthored numerous books, including The Relaxation and Stress Reduction Workbook, Self-Esteem, Thoughts and Feelings, When Anger Hurts, and ACT on Life Not on Anger. McKay received his PhD in clinical psychology from the California School of Professional Psychology, and specializes in the cognitive behavioral treatment of anxiety and depression. He lives and works in the greater San Francisco Bay Area.