In 2000, Bill Campbell retired as CEO of Intuit, the software company. He’d had a long and interesting career—as a failed Ivy League football coach, a salesman at Kodak, a board member at Apple—but he was about to embark on one of the most storied second acts in American business. Campbell was recruited by Kleiner Perkins, the Silicon Valley venture capital fund, to act as a coach-in-residence for its portfolio companies. And so Campbell began working with Eric Schmidt, then the newly recruited CEO of Google, as well as its founders, Larry Page and Sergey Brin, meeting with them as frequently as once a week to work through the challenges of building a young company. Campbell also served as a coach of a Who’s Who of Silicon Valley, working with Steve Jobs at Apple, John Donahoe at eBay, Ben Horowitz of Andreessen Horowitz, Dick Costolo of Twitter, and even Al Gore, in his post-government life. In their new book, Trillion Dollar Coach, Schmidt—now retired—and fellow Google executives Johnathan Rosenberg and Alan Eagle make the case that Campbell is one of history’s greatest coaches, and through his influence on Google and Apple, instrumental in creating $2 trillion worth of value. The key, they write, was that Campbell didn’t mentor individuals but coached teams. He involved himself in their decisions, pointed out their mistakes, and acted as an honest broker in helping resolve disputes. Importantly, he helped them imagine the best version of themselves and held them to account when they fell short. Quartz interviewed Schmidt about the lessons Campbell offers all managers, his time serving on the Apple board with Jobs, and whether Silicon Valley is suffering from a crisis of leadership.