Co-CEO, co-chief investment officer, Bridgewater Associates
Age: 36
Rank change: New
Industry: Finance
Jensen interned at Bridgewater while an undergrad at Dartmouth. Now he works alongside legendary founder Ray Dalio at the world's largest hedge fund (assets under management: $88 billion) overseeing research and trading. Like Dalio, who lives by 300 principles spelled out on the company's website, Jensen has a self-reflective side: He credits his steep trajectory to the firm's mission to seek the truth -- whether that means what's really driving the economy or one's own weaknesses and flaws.
Fan of: Paul Krugman and Paul Volcker -- though he doesn't always agree with them.
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Last updated October 14 2010: 1:25 PM ET