The liberating effect of failure

Failure is the crucible that makes a leader into a hero, says Yale's Jeffrey Sonnenfeld.
 Jeffrey Sonnenfeld knows failure. A professor at the Yale School of Management and founder of the non-profit Chief Executive Leadership Institute, Sonnenfeld has risen to leadership-guru status by becoming the expert on how CEOs stumble and bounce back. He first explored failure 20 years ago in his book "The Hero's Farewell: What Happens When CEOs Retire." Sonnenfeld's latest, "Firing Back: How Great Leaders Rebound After Career Disasters," hits the topic head on. Fortune editor at large Patricia Sellers talked with Sonnenfeld about what he has learned studying failure.