Rosenfeld made a big show of power this year with her decision to split Kraft into two companies, a reversal of her previous strategy of expanding through acquisitions (like the 2010
purchase of Cadbury). Her new role hasnít been decided but she plans to remain CEO until the dealís expected close in 2012.
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.