Jonah Berger is an internationally bestselling author and marketing professor at the University of Pennsylvania's Wharton School. His books include Contagious, Invisible Influence, and The Catalyst. He has published over 50 papers in top-tier academic publications and is a world-renowned authority on social impact, word of mouth, and why things, ideas, and behaviors take on. He's worked as a consultant for a number of Fortune 500 businesses and keynoted hundreds of events, and his work has been featured in publications such as The New York Times, The Wall Street Journal, and Harvard Business Review. His research was also included in the Year in Ideas issue of the New York Times Magazine.