David LeFevre Dodd (August 23, 1895 September 18, 1988) was an American educator, financial analyst, author, economist, professional investor, and in his student years, a protégé of, and as a postgraduate, close colleague of Benjamin Graham at Columbia Business School. He attended the University of Pennsylvania. The Wall Street Crash of 1929 (Black Thursday) almost wiped out Graham, who had started teaching the year before at his alma mater, Columbia. The crash inspired Graham to search for a more conservative, safer way to invest. Graham agreed to teach with the stipulation that someone take notes. Dodd, then a young instructor at Columbia, volunteered. Those transcriptions served as the basis for a 1934 book Security Analysis, which galvanized the concept of value investing. It is the longest running investment text ever published.