My goal is very clear, and I wrote about it in Lean In, which is that women run half our companies and countries and men run half our homes. As much as I wish that could happen in four years, I don't think that's a likely time period. But I think it can happen sooner than we think. Part of it is having that aspiration and that goal. I think we too often suffer from the tyranny of low expectations.

You know, there has never been a 24-hour period in five years when I have not responded to e-mail at Facebook. I am not saying it's easy. I work long hours.

Two things that I think matter are gratitude and joy.

Motivation comes from working on things we care about. It also comes from working with people we care about.

But the upside of painful knowledge is so much greater than the downside of blissful ignorance.

The gender stereotypes introduced in childhood are reinforced throughout our lives and become self-fulfilling prophesies. Most leadership positions are held by men, so women don't expect to achieve them, and that becomes one of the reasons they don't.

We call our little girls bossy. Go to a playground; little girls get called bossy all the time - a word that's almost never used for boys - and that leads directly to the problems women face in the workforce.