Robert A. Emmons, PhD, is a professor of psychology at the University of California, Davis, where he has taught for the past thirteen years. In his research, he explores how religiousness and spirituality may reflect core aspects of identity and how these aspects of self are involved in well-being and personality. He is the author of over sixty research articles and book chapters. His most recent book is the Psychology of Ultimate Concerns: Motivation and Spirituality in Personality.