Berger, Jonah: - Jonah Berger is a marketing professor at the Wharton School at the University of Pennsylvania and internationally bestselling author of Contagious, Invisible Influence, and The Catalyst. He's a world-renowned expert on social influence, word of mouth, and why products, ideas, and behaviors catch on and has published over 50 papers in top-tier academic journals. He has consulted for a range of Fortune 500 companies, keynoted hundreds of events, and popular accounts of his work often appear in places like The New York Times, The Wall Street Journal, and Harvard Business Review. His research has also been featured in the New York Times Magazine's "Year in Ideas."