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3. Greg Jensen
Greg Jensen
Co-CEO and co-CIO, Bridgewater Associates
Age: 37
Industry: Finance

Jensen's work overseeing research at the world's largest hedge fund (assets under management: $125 billion) has paid off. Bridgewater's flagship fund is up 25%, while many marquee names are losing money. Jensen also oversaw the rollout of the $10 billion fund Pure Alpha Major Markets in June. Jensen, who started at Bridgewater as an intern while at Dartmouth, believes the firm's unusual culture (articulated by founder Ray Dalio in the form of 300 self-help principles) is the key to the firm's success -- and his own.

Last updated October 25 2011: 5:11 PM ET
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