 Driehaus attended high school at St. Ignatius College Prep and received his undergraduate (1965) and master's (1970) degrees in business from DePaul University.He also received an honorary doctorate degree from DePaul in 2002.After graduation, Driehaus was an assistant to the director of research at local broker Rothschild & Co.

From 1968 through 1973, Driehaus developed research ideas for the institutional trading department at A.G. Becker & Co.