Stephen L. Weiss is a partner at an investment bank in New York. During a career that spans nearly 25 years, he has been a hedge fund manager and has held senior management positions at some of Wall Street's most prestigious firms including Salomon Brothers, SAC Capital, and Lehman Brothers. Mr. Weiss' book, The Billion Dollar Mistake: Learning the Art of Investing from the Missteps of Legendary Investors, profiles 10 extremely successful investors who have made very significant mistakes, often costing billions of dollars. He explores each individual's background, the particular investment that went awry and then distills the mistake into lessons for the average investor. These garden variety mistakes differ from those made by the average investor only by their magnitude - the number of zeros to the left of the decimal point.