The Master Key System
Charles Haanel
The Master Key System is a personal development book by Charles F. Haanel that was originally published as a correspondence course in 1912. Though originally a 24 week correspondence course, it was first published as a book in 1916 by Psychology Publishing, St. Louis and The Master Key Institute, New York.Along with "The Science of Getting Rich", by Wallace D. Wattles, the Master Key System is the source of Rhonda Byrne's inspiration for the book and the film "The Secret" (2006). Charles F. Haanel was an American author, millionaire, entrepreneur, and businessman who belonged to several Masonic societies, the American Scientific League, The Author’s League of America, The American Society of Psychical Research, the St. Louis Humane Society, and the St. Louis Chamber of Commerce.