Philanthropy is not about the money. It's about using whatever resources you have at your fingertips and applying them to improving the world.

[Bill Gates] wanted me to stay working at Microsoft, but I didn't think he could be CEO and we could have the family life that we both had growing up, which is what we envisioned. I knew I would go back to work at some point later to some profession. I just didn't know what.

When I look at 225 million women who want contraceptives, and then I look at the 52 million unintended pregnancies that could be avoided by addressing this unmet need, where can we have the biggest impact with our voice, our dollars, our partners? It's on contraceptives. I would rather address the problem upstream.

If you can't travel to the developing world, look at helping to fund a woman with a small loan and follow her. Learn her story. Learn about the difference that you're making.

In places like India with smartphones, there's an app now for women if they're in a violent situation, they can press one button. They've given their cell-phone number to five trusted friends, and right away their GPS location goes out: "Here I am."

If you invest in a girl or a woman, you are investing in everybody else.

Now, as smartphones are coming up, there are all kinds of apps that will start to be developed that will help women.