For the first five decades of my life, I was, at various points, a computer science nerd, a Microsoft executive, a full-time mom, and a co-chair of the foundation Bill and I started together. But on my 50th birthday, I made a promise to myself that the rest of my life would have one central focus: improving the lives of women and girls around the world.

That's why I'm joining up with MarieClaire.com as a contributing editor: I'll report from the front lines about how the world is changing for women—and how it should change more. I want to spark smart conversations with you about what it means to be a woman today (and tomorrow), whether here in the U.S. or in rural villages in some of the world's poorest places.

These conversations are more important than ever because people are finally listening. We're in the midst of an international movement for gender equality unlike anything the world has ever seen.

Read More at www.marieclaire.com