Chris Zook, partner at Bain & Company and co-head of the firm's global strategy practice.

Tom Davenport, Babson College professor and coauthor of "Judgment Calls: Twelve Stories of Big Decisions and the Teams That Got Them Right."

Avivah Wittenberg-Cox, CEO of the consultancy 20-first and author of "How Women Mean Business."

Charlotte Fritz, assistant professor at Portland State University.

Christiane Amanpour, renowned war correspondent and news anchor.

Ken Favaro, senior partner at Booz & Company and coauthor of the HBR article "Creating an Organic Growth Machine."

Ian Bremmer, president of Eurasia Group and author of "Every Nation for Itself: Winners and Losers in a G-Zero World."

Daniel Gross, columnist and economics editor for Yahoo! Finance and author of "Better, Stronger, Faster: The Myth of American Decline . . . and the Rise of a New Economy."

Paul Polman, CEO of Unilever.

Marcus Buckingham, founder of TMBC and author of "StandOut."

Grant McCracken, anthropologist and author of "Culturematic: How Reality TV, John Cheever, a Pie Lab, Julia Child, Fantasy Football . . . Will Help You Create and Execute Breakthrough Ideas."

Michael Schrage, research fellow at MIT Sloan School's Center for Digital Business and author of the HBR Single "Who Do You Want Your Customers to Become?"

Don Thompson, economist and author of "Oracles: How Prediction Markets Turn Employees into Visionaries."

Sallie Krawcheck, former president of Bank of America Global Wealth & Investment Management and author of the HBR article "Four Ways to Fix Banks."

Boris Groysberg and Michael Slind, authors of "Talk, Inc.: How Trusted Leaders Use Conversation to Power Their Organizations."

Andrew Zolli, director of PopTech and coauthor of "Resilience: Why Things Bounce Back."

Susan Cain, author of "Quiet: The Power of Introverts in a World that Can't Stop Talking."

Sally Ride, former NASA astronaut and founder of Sally Ride Science.

Dan McGinn, HBR senior editor and author of the article "Too Many Pivots, Too Little Passion."

Frank Partnoy, professor of law and finance at the University of San Diego and author of "Wait: The Art and Science of Delay."

Cassie Mogilner, assistant professor of marketing at the Wharton School and author of the HBR article "You'll Feel Less Rushed If You Give Time Away."

Frank Barrett, jazz pianist and author of "Yes to the Mess: Surprising Leadership Lessons from Jazz."

Russ Feingold, former US senator from Wisconsin and founder of Progressives United.

Nilofer Merchant, author of "11 Rules for Creating Value in the Social Era."

Tom Ricks, journalist and author of the HBR article "What Ever Happened to Accountability?"

Michael Silverstein, cofounder of The Boston Consulting Group's global consumer practice and coauthor of "The $10 Trillion Prize."

Dorie Clark, strategy consultant and author of the HBR article "A Campaign Strategy for Your Career."

Kevin Boudreau, London Business School professor.

Nate Silver, statistician and founder of The New York Times political blog FiveThirtyEight.com.

Gary Pisano, Harvard Business School professor and coauthor of "Producing Prosperity: Why America Needs a Manufacturing Renaissance."

Jodi Glickman, founder of the communication training firm Great on the Job and contributor to the "HBR Guide to Getting a Job."

Nancy Koehn, Harvard Business School historian and editor of "The Story of American Business."

Tom and David Kelley, leaders of IDEO and authors of the forthcoming HBR article "Reclaim Your Creative Confidence."

James Allworth, regular contributor to HBR and coauthor of the Nieman Reports article "Breaking News: Mastering the Art of Disruptive Innovation in Journalism."

Gautam Mukunda, Harvard Business School assistant professor and author of "Indispensable: When Leaders Really Matter."

Maxwell Wessel, fellow at the Forum for Growth and Innovation and coauthor of the HBR article "Surviving Disruption."

Chrystia Freeland, editor of Thomson Reuters Digital and author of "Plutocrats: The Rise of the New Global Super-Rich and the Fall of Everyone Else."

Alexandra Samuel, vice president of social media at Vision Critical.

Jeff Bezos, CEO of Amazon.com.

Tim Sullivan, editorial director of Harvard Business Review Press and coauthor of "The Org: The Underlying Logic of the Office."

John Mackey, co-CEO of Whole Foods Market and coauthor of "Conscious Capitalism: Liberating the Heroic Spirit of Business."

Christine Porath, associate professor at Georgetown University's McDonough School of Business and coauthor of the HBR article "The Price of Incivility."

Jeanne Meister, partner at Future Workplace and contributor to the "HBR Guide to Managing Up and Across."

Jorge Cauz, president of Encyclopaedia Britannica.

Daniel Pink, author of "To Sell Is Human" and the HBR article "A Radical Prescription for Sales."

Mary Robinson, former President of Ireland.

Bryan Garner, editor in chief of Black's Law Dictionary and author of the "HBR Guide to Better Business Writing."

Bruce Nussbaum, professor at Parsons The New School of Design and author of "Creative Intelligence: Harnessing the Power to Create, Connect, and Inspire."

Sheryl Sandberg, Facebook COO and author of "Lean In: Women, Work, and the Will to Lead."

Elizabeth Grace Saunders, founder and CEO of Real Life E and author of "The 3 Secrets to Effective Time Investment."