Davies made her name at Microsoft where she was CFO for its then-$29 billion Platform and Services Division -- one of its most profitable.
She was tapped to join the turnaround at $7.5 billion insurance broker Aon in 2007. Since then she's closed its underwriting businesses and overseen a massive restructuring with more than 3,600 job cuts.
The turnaround seems to be working: its stock is up 17% since 2007 and earning rose 70% in 2008 from 2007.
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