25 most powerful people in business

Chairman and CEO, JP Morgan Chase

While Citigroup, Wachovia, and Bank of America struggle with multibillion-dollar losses, one big bank is emerging relatively unscathed from the market meltdown: J.P. Morgan Chase. That is a tribute to Jamie Dimon, its CEO since early 2006. "I think we're fine," he told a conference in mid-November. The market surely believes he is the man of the moment: Over the past three months, J.P. Morgan's stock has fallen, but it has still outperformed its major rivals.

Dimon has always shown a mastery of risk management. From 1975 to 1998 he was Sandy Weill's partner in creating the world's biggest financial services firm, Citigroup. It was Dimon who played hands-on operator to Weill's dealmaker by integrating a dazzling string of acquisitions. Fired in 1998, he rescued Chicago's Bank One, then merged with J.P. Morgan in 2004. With Citi in a swoon, Dimon is getting a sweet taste of revenge. --Shawn Tully