President and CEO
IBM
2011 rank: 7
Age: 55
A 31-year IBM veteran, Rometty has been a key supporting player in some of Big Blue's biggest transformations: She managed the $3.5 billion PwC Consulting acquisition that launched IBM in the services business, and with chairman Sam Palmisano worked to develop the five-year growth plan. As CEO, she's now in charge of delivering on it.
By Beth Kowitt, Colleen Leahey, and Anne VanderMey.