After Martina Hund-Mejean was hired in November 2007, one of her many initiatives at MasterCard included starting up a job rotation program among the 700 people in her department. Implementing it was not easy. "This is not something where you can turn on a switch and everybody rotates," she says. "It's a culture change you have to foster."

Described as thorough and direct, Hund-Mejean, 50, first picked some people she thought would do well with a change. She also made sure to include upper management, middle managers and rank and file. By the rotation's second year, 17 percent of employees in the group changed roles. "Developing talent is paramount," Hund-Mejean says. "You are developing people who can take a higher position, rather than having to go out on the market and hire someone."

Hund-Mejean grew up in Germany, where her mother got her a job at 13 as a dishwasher at a local fish restaurant. At 14, she moved on. "My mom let me graduate to a bakery and I got rid of the smell," she says. She also taught math on the side, which helped her finance trips abroad to learn English in the U.K. and U.S.

After getting an MBA at the University of Virginia, she held finance posts at General Motors Corp., Lucent Technologies Inc. and Tyco International Ltd., helping them all emerge from financial trouble at one time or another. At MasterCard, Hund-Mejean continues to revel working with a team on an acquisition or guiding her own group.

"I have to have fun on the job," she says. "The fun is provided by the people I work with."

Subscribe Now

Access to authoritative analysis and perspective and our data-driven report series.

14-Day Free Trial

No credit card required. Complete access to articles, breaking news and industry data.