Can you identify the one person, event or influence that made you who you are as a leader and person? Over the past decade, I've posed this question to 100 of the people I've represented as chairman of the Washington Speakers Bureau, including former US secretaries of states Madeleine Albright, Colin Powell and Condoleezza Rice; former NFL quarterback Terry Bradshaw; and news correspondent Tom Brokaw. I wanted to know what they considered their turning points – the moments and influences that still inspire and motivate them.

I found that the turning points fell into three broad categories: