Managers told us repeatedly that they would bend over back­ward to retain women who add value. It seems obvious to us. You are in a much stronger position to demand the work life you want if your company wants to keep you. Let’s not kid ourselves. If your bosses think you’re of marginal benefit, they’re going to be happier to let you go than to disrupt their carefully organized office routine to satisfy you.

Chances are, however, that you do add value, and we suspect your biggest problem, as a woman, is not that you don’t perform but that you don’t appreciate just how needed you are. That’s the case for the vast majority of women we’ve spoken to.

However, just to be sure, take stock of your performance—in any job there are ways to measure performance. How are your annual appraisals? Do you meet your sales targets? Have your bosses complimented your work? Are you someone they turn to with confidence? Do you shape the discussion at your company strategy meetings? Do they happily put you in front of clients? Have you been promoted recently? Do you get face-time with higher-ups? How easy would it be to replace you? You may need to spend a number of months making yourself invaluable.

If you’re feeling at all nervous, chuck a little confidence and pride into the negotiating mix. We love Linda Brooks’ story about how she negotiated her two-thirds law partner deal— almost unheard of in her circles.

Linda simply gave them no wiggle room, and it worked. “I said, ‘I have to go flextime, I want flextime.’ Actually, I don’t even think they would have negotiated if I had said it in less stark terms,” she admits. “But I just said, ‘This is what I want to do,’ and they said, ‘Specifically, what percentage of time off do you want,’ because with our firm it’s all a time-percentage thing, and I said, ‘Two-thirds time.’ Which means I leave a third of the profits behind. And they said, ‘For how long?’ and I said, ‘In­definitely.’ They were convinced then, I’m sure, that it was just a passing phase.” She laughs. “But now I can’t ever see myself going back, I’m happier than I’ve ever been.”

For women in their thirties and forties, this is the time to really push for your New All because your stock has never been higher. You have years of super valuable experience in your field and quite possibly years in your company too. You can’t be re­placed by an inexperienced twenty-five-year-old, and your com­pany needs your longevity. So these are the years to max out on your value and demand all the time you need. Linda Brooks was nearing forty and already a partner when she got her new life— it was the ideal time to up the ante: “I got what I wanted because I already had power. So what were they going to do?”