Akira Watanabe: Chief executive officer, Tokyo-Mitsubishi International

Akira Watanabe was the pioneer of derivatives in Japan and founded many of Mitsubishi's investment-banking activities. Now he aims to double the size of Tokyo-Mitsubishi International within the next three years and challenge Nomura International's supremacy among Japan's global investment banks.

Known, even in official meetings, as "Wani" ­ crocodile or alligator in Japanese ­ his bubbly, genial exterior masks a ferocious competitive streak and an acute intellect. "They think it's appropriate because I'm sort of dangerous ­ aggressive," he beams.

"Once he bites he won't let go," says a London-based Japanese banker. "He's the type who never gives up in what he's trying to achieve." A colleague adds: "Unlike the traditional Japanese way ­ seeking consensus first ­ he'll take decisions and defend them later."

Watanabe was vice-chairman of the International Swap Dealers Association from 1989 to 1993 and is now on the boards of the International Primary Market...