In 1975, James joined investment bank Donaldson, Lufkin & Jenrette and became head of the firm's global M&A group in 1982. He founded DLJ Merchant Banking, Inc. in 1985. In 1995, James was appointed chairman of the firm's banking group, a position he held when DLJ was acquired in 2000 by Credit Suisse First Boston, and was a member of its board of Directors. At CSFB, James served on the executive board and as chairman of global investment banking and private equity. A 2007 Wall Street Journal article credited James with leading the acquisition process, on behalf of DLJ.