Bill [Gates] and I believe philanthropy can only be effective if it starts things and proves whether they actually work or not. That's the place that governments often don't want to, or can't, work.

After a number of years dating, we decided we were good partners.

I'm happy we have three healthy children and we'll stay with three healthy children.

Sanitation issues in the developing world affect women more than they affect men.

What great changes have not been ambitious?

It's important to remember that behind every data point is a daughter, a mother, a sister—a person with hopes and dreams.

My background was computer science and business school, so eventually I worked my way up where I was running product groups - development, testing, marketing, user education.