Revenues at Russia's natural gas monolith - ranked 47 on Fortune's Global 500 - grew by 21.6% in 2007 to $98.6 billion. The state-owned company employs more than 400,000 workers and controls at least a quarter of the world's gas reserves. But CEO Alexei Miller faces a massive challenge: The company's production is stagnating while global demand soars. Gazprom has acknowledged that output will plateau through 2009 but moved in late August to increase its investment in exploration by $40 billion.
By Mina Kimes
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