The Master Key System is a personal development book by Charles F. Haanel (1866-1949). It was originally released as a 24-week correspondence course in 1912, and then published in book form in 1916. Each of the 24 chapters contains an introduction, an exercise, and a concludes with questions and answers.The book is a set of lessons that cover a wide range of topics, including the power of thought, the laws of success, and the nature of the universe.
At the core of the book is the idea that the universe is governed by certain laws, and that we can harness these laws to achieve success and abundance in our lives. Haanel argues that by understanding and applying these principles, we can tap into an unlimited source of power and create the lives we desire.
Throughout the book, Haanel explores a range of topics, including the power of concentration, the role of the subconscious mind, and the importance of goal setting. He also offers practical exercises and techniques that readers can use to apply these principles in their own lives.
In 1919, Napoleon Hill wrote a letter to Charles F. Haanel about the influence that The Master Key System had on him. In the letter Hill wrote "I believe in giving credit where it is due, therefore I believe I ought to inform you that my present success and the success which has followed my work as President of the Napoleon Hill Institute is due largely to the principles laid down in The Master-Key System."