Online Extra: Q&A with CSFB's John Mack

When John J. Mack took charge of investment bank Credit Suisse First Boston last July, it was in big trouble. The freewheeling bank had become a symbol of the initial public offering con game and was headed for a $1 billion loss. Worse, internal warfare resulting from CSFB's purchase of rival Donaldson, Lufkin & Jenrette for $12 billion in 2000 was tearing it apart.

Mack has brought CSFB back from the brink, but now he wants to transform it from one of Wall Street's most troubled investment banks into one of its most credible. To achieve that, at a bare minimum, Mack must show that CSFB is well-managed and profitable. Mack recently shared some of his plans for doing that with BusinessWeek Investment Banking Editor Emily Thornton. Here are edited excerpts of their conversation: