Vice chairman and director, FMR LLC; President, Fidelity Personal, Workplace, and Institutional Services Fidelity Investments 2010 rank: 21 Age: 49
The financial services giant is mum about succession, but Johnson, who oversees $3.5 trillion in assets, may have stepped closer to the top spot when her 81-year-old father, Fidelity
Investments and FMR CEO Ned, gave up one of his board posts this spring.
The list is compiled by FORTUNE editors, who consider four criteria: the size and importance of the womanís business in the global economy, the health and direction of the
business, the arc of the womanís career (resume and runway ahead), and societal and cultural influence.