Sunil Gupta, Harvard Business School professor, has spent years studying successful digital strategies, companies, and leaders, and he's made Amazon and its legendary CEO Jeff Bezos a particular areas of focus. Drawing on his own in-depth research and other sources, including a new collection of Bezos' own writing, "Invent and Wander," Gupta explains how Amazon has upended traditional corporate strategy by diversifying into multiple products serving many end users instead of focusing more narrowly. He says that Bezos's obsession with the customer and insistence on long-term thinking are approaches that other companies and senior executives should emulate.