“I am never bored,” McCarthy says. “On any given day, I can be switching around pretty quickly.”

Handling it all wouldn't be possible without “an excellent staff” of nine direct reports, McCarthy says, as well as the ability to focus intently on whatever task is at hand.

Recently, prioritizing day to day has meant keeping her treasury responsibilities, especially capital markets, on the agenda, because of critical projects such as financing Disney's first theme park in mainland China, in Shanghai.

“The one area that is always top of mind for me are my treasury responsibilities, and that's because so many of those areas are market related, or large-scale project related,” McCarthy says.

Like so many companies, Disney has been focusing on building its business in China, and McCarthy has been busy finding ways for the company to more easily work with customers and suppliers there. Earlier this year, when Disney renewed its corporate credit facility, it included three major Chinese banks in the syndicate for the first time. “That's a significant change in the way we're working with the Chinese,” she says.

It may seem a departure for a former biology major at Smith College to end up as treasurer at one of the world's largest media and entertainment companies. But McCarthy, who also earned a M.B.A. in marketing and finance from the Anderson School of Management at UCLA, says learning the scientific method and performing research in the lab prepared her well for a corporate finance career.

Indeed, she remains an advocate of encouraging women to study math and the sciences, and recently mentored a woman engineering major at Caltech. In part because of McCarthy's encouragement, that student will go on to a graduate management science and engineering program.

The similarities between biology and corporate finance lie in the “disciplined approach to problem-solving,” McCarthy says.

“Applying the scientific method to problem-solving doesn't have to be restricted to lab experiments,” she notes. “When you're going through problems, you quickly throw out irrelevant factors, and focus on the things that really make a difference. That training early on in your career can really be well-applied in business.”