21. Raj Shah
Raj Shah
Administrator, U.S. Agency for International Development (USAID)
Age: 38
Industry: Government

The American foreign-aid chief faced his first major crisis just days after his swearing-in, when an earthquake wrought biblical-scale destruction in Haiti. There has been no shortage of international challenges since, but the University of Pennsylvania-trained doctor and MBA is at least as focused on internal reforms to a notoriously inefficient bureaucracy. Applying the entrepreneurial discipline he learned at the Gates Foundation, Shah is working to reorient American foreign aid toward sustainable, private-sector approaches.

Big fan of: American sports cars. (His father worked for Ford.)

Last updated October 25 2011: 5:11 PM ET
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