The Master Key System (Classic Hardback Collector’s Edition) by Charles Haanel

• ISBN-: ‎ 978-8182475649
• Editon-: 2021
• Page-: 168

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 published in book form in 1916. 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.