Robert A. Emmons, Ph.D., is the world’s leading scientific expert on gratitude. He is a professor of psychology at the University of California, Davis, and the founding editor-in-chief of The Journal of Positive Psychology. He is the author of the books Thanks! How the New Science of Gratitude Can Make You Happier, Gratitude Works!: A 21-Day Program for Creating Emotional Prosperity, and The Little Book of Gratitude.