Frances Hesselbein

Hesselbein rose to fame as CEO of the Girl Scouts of the USA, which she transformed in the 1960s and 1970s—an achievement for which she got the Presidential Medal of Freedom. In her late 90s, she continues to train a new generation of leaders through her eponymous institute. It’s a lucky thing. After all, who else can reframe the work of the late Peter Drucker for an audience of millennials? (Yes, that’s her latest book.)