Credit Suisse received more money from the rich than any other private bank last year and has its sights on toppling UBS as Switerland’s top private bank. but can Walter Berchtold sustain its success as the financial crisis recedes?

In an elegant walnut-panelled meeting room in Credit Suisse's headquarters on the Paradeplatz in Zurich, Walter Berchtold looks out of the window at the headquarters of the bank's greatest rival, UBS, across the square and smiles.