Og Mandino was a legendary American author and motivational speaker best known for his classic bestseller, The Greatest Salesman in the World. With over 50 million books sold globally, he is an authority on personal success and salesmanship. A former president of Success Unlimited magazine and a National Speakers Association Hall of Fame inductee, Mandino’s teachings on perseverance and self-discipline were forged through his own dramatic journey from despair to international influence.