Leaders are no strangers to challenges; in recent years, businesses have experienced unprecedented layoffs, dismal sales, dwindling retirement accounts, and the bankruptcy of once-heralded institutions. While these uncertain times are difficult, they also provide the opportunity for great leadership. Over three decades of research, Jim Kouzes and Barry Posner, the bestselling authors of The Leadership Challenge, have asked thousands of leaders to describe their personal leadership best. Across the board, people say their greatest moments arise out of the most difficult periods of their careers.