40 Under 40: Meet their mentors

The members of our 40 Under 40 list wouldn't have gotten to where they are without some sage advice. Here's who they turn to for guidance.

Ray Chambers
Ray Chambers

Jack Dorsey met his mentor Ray Chambers though a New York acquaintance, and has been working with him monthly for over six months. Chambers made his fortune via a private equity firm called Wesray Capital Corp. that he co-founded in 1981. He's currently involved in many kinds of philanthropy, and serves as the Special Envoy of the Secretary-General for Malaria.

By Shelley DuBois, writer-reporter - Last updated October 24 2011: 2:41 PM ET