One of the greatest personal development books ever written and a foundation of the self-help genre, The Master Key System explains how to harness the power of thought in order to achieve your goals and cultivate new skills. This bestseller forms the original course in New Thought, promising benefits such as advances in mental development and improvements in physical health and finances. Its timeless teachings employ the law of attraction and creative visualization, concepts later adapted by Napoleon Hill (Think and Grow Rich) and Rhonda Byrne (The Secret).