CLAYTON M. CHRISTENSEN (1952–2020) was the Kim B. Clark Professor at Harvard Business School, the author of nine books, a five-time recipient of the McKinsey Award for Harvard Business Review’s best article, and the cofounder of four companies, including the innovation consulting firm Innosight. In 2011 and 2013 he was named the world’s most influential business thinker in a biennial ranking conducted by Thinkers50.