Gabriella Rosen Kellerman, MD, has served as chief product officer and chief innovation officer at BetterUp, founding CEO of LifeLink, and an advisor to healthcare, coaching, and behavior change technology companies. Trained in psychiatry and fMRI research, she holds an MD with honors from Mount Sinai School of Medicine and a BA summa cum laude from Harvard University. Her work has been published and featured in The Atlantic Online, Harvard Business Review, Inc., Forbes, and many more. Tomorrowmind is her first book. Martin Seligman, PhD, is a professor at the University of Pennsylvania, director of the Positive Psychology Center, and former president of the American Psychological Association. He received his BA in philosophy from Princeton University, and his PhD in psychology from the University of Pennsylvania and holds ten honorary doctorates. He was named the most influential psychologist in the world by Academic Influence. Along with writing for numerous scholarly publications and appearing in The New York Times, Time, Newsweek, and many others, he is also the author and coauthor of over thirty books, including Flourish, Authentic Happiness, and Tomorrowmind.