The Swiss banking giant's latest appointment is a surprise, as there had been several more experienced and higher profile candidates in the running.
Mr Dougan, 44, has worked for the bank for 15 years, running its equities unit, debt arm and the investment banking division. He now becomes the youngest chief executive of any Wall Street investment bank, moving from his current post as head of investment banking.
The new chief executive takes over the helm on May 5th, replacing Mr Grubel, who had been expected to hold the post for at least two years, but now plans to retire.
John Mack, who was appointed from Morgan Stanley to turn around the company's fortunes, left Credit Suisse in June last year after three years in charge, after the board refused to support his proposals for a merger with a leading rival and the bank lost market share.
Credit Suisse First Boston has also revealed that Paul Calello will become the new chief executive of investment banking and Robert Shafri is taking over as chief executive of the Americas.