CYNTHIA A. MONTGOMERY is the Timken Professor of Business Administration and immediate former head of the Strategy Unit at Harvard Business School, where she’s taught for twenty years. For the past six years, she has led the strategy track in the school’s highly regarded executive program for owner-managers, attended by business leaders of midsized companies from around the globe. She has received the Greenhill Award for her outstanding contributions to the Harvard Business School’s core MBA strategy course. Montgomery is a top-selling Harvard Business Review author, and her work has appeared in the Financial Times, American Economic Review, Rand Journal of Economics, Strategic Management Journal, Management Science, and others. She has served on the boards of directors of two Fortune 500 companies and a number of mutual funds managed by BlackRock, Inc.