We have a problem with women in leadership across the board. This leadership gap - this problem of not enough women in leadership - is running really deep and it's in every industry. My answer is we have to understand the stereotype assumptions that hold women back.

Women have made tons of progress. But we still have a small percentage of the top jobs in any industry, in any nation in the world. I think that's partly because from a very young age, we encourage our boys to lead and we call our girls bossy.

The reason I wrote Lean In is I think people weren't actually noticing that we had stopped making progress. I gave a TED talk and said: "It turns out men still run the world." And the audience gasped as if that was news.

Trying to do it all and expecting that it all can be done exactly right is a recipe for disappointment. Perfection is the enemy.

At Facebook we feel a lot of affinity not just for this community but for any community that is trying to do what Davos is trying to do, which is to share information. And Davos is doing it in a particular way - I think the Facebook approach is obviously more broad-based, we're trying to include everyone in the world. But the goal is the same: bring people together, to share information and make the world more connected, and have people have a deeper understanding of themselves, others, the communities of which they want to be a part and can be a part.

All of us want the same things. We want to be good to the people around us and for our lives to have meaning. For me that means making the world a little bit easier for women.

Grief affects job performance, so giving workers time off to grieve can lead to stronger outcomes at work.