CEO, GE Transportation
Age: 37
Rank change: Down
Industry: Industrial
GE's youngest-ever division head has run its $4 billion transportation business since 2008. In those two years Simonelli, a native of Florence, Italy, has been fighting a brutal market for the locomotives and large engines that his business makes: Revenue was down 34% in the latest quarter. But there may be a light at the end of the tunnel: Orders jumped 84% to $1.2 billion. Simonelli may not be around to enjoy a turnaround -- his predecessors have lasted two or three years before being promoted within GE.
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Last updated October 14 2010: 1:25 PM ET