Think and Grow Rich was written by Napoleon Hill in 1937 and promoted as a personal development and self-improvement book. He claimed to be inspired by a suggestion from business magnate and later-philanthropist Andrew Carnegie.  First published during the Great Depression, this book has sold more than 15 million copies  It remains the biggest seller of Napoleon Hill's books. Business Week magazine's Best-Seller List ranked it the sixth best-selling paperback business book 70 years after it was published.Think and Grow Rich is listed in John C. Maxwell's A Lifetime "Must Read" Books List.  While the book's title and much of the writing concerns increasing income, the author insists that his philosophy can help people succeed in any line of work, to do and be anything they can imagine.  Think and Grow Rich is based on Hill's earlier work The Law of Success, said to be the result of more than twenty years of study of many individuals who had amassed personal fortunes.  Hill studied their habits and drew some 16 "laws" to be applied to achieve success. Think and Grow Rich condenses them, providing the reader with 13 principles in the form of a "Philosophy of Achievement". The book asserts that desire, faith, and persistence can propel one to great heights if one can suppress negative thoughts and focus on long-term goals.