Og Mandino (December 12, 1923 – September 3, 1996) was an American author. He wrote the bestselling book The Greatest Salesman in the World. His books have sold over 50 million copies and have been translated into over twenty-five different languages. He was the president of Success Unlimited magazine until 1976 and is an inductee of the National Speakers Association's Hall of Fame.
Mandino wrote The Greatest Salesman in the World which contains the "time-tested wisdom of the ancients distilled into ten simple scrolls" which, if followed for the prescribed ten months, will as Og says, "seep into my other mind, that mysterious source which never sleeps, which creates my dreams, and often makes me act in ways I do not comprehend. As the words of these scrolls are consumed by my mysterious mind I will begin to awake, each morning, with a vitality I have never known before. My vigor will increase, my enthusiasm will rise, my desire to meet the world will overcome every fear I once knew at sunrise, and I will be happier than I ever believed it possible to be in this world of strife and sorrow." The scrolls each have a principle designed to replace bad habits built up over a lifetime which "threatens to imprison my future" with good habits developed through a ten-month process of studying the scrolls.