The real women's issue: Time

In her much-discussed new book, Facebook Chief Operating Officer Sheryl Sandberg tells women with high aspirations that they need to “lean in” at work—that is, assert themselves more. It’s fine advice, but it misdiagnoses the problem. It isn’t any shortage of drive that leads those phalanxes of female Harvard Business School grads to opt out. It’s the assumption that senior roles have to consume their every waking moment. More great women don’t “lean in” because they don’t like the world they’re being asked to lean into.

It doesn’t have to be this way. A little organizational imagination bolstered by a commitment from the C-suite can point the path to a saner, more satisfying blend of the things that ambitious women want from work and life. It’s time that we put the clock at the heart of this debate.

I know this is doable because I run a growing startup company in which more than half the professionals work fewer than 40 hours a week by choice. They are alumnae of top schools and firms like General Electric and McKinsey, and they are mostly women. The key is that we design jobs to enable people to contribute at varying levels of time commitment while still meeting our overall goals for the company.