Invest in You: Ready. Set. Grow.

Greta Gerwig on negotiating: I was scared to ask for too much

Greta Gerwig: How movie directors use salary negotiations to bet on themselves

Greta Gerwig isn't always comfortable negotiating her salary.

Even with her agent acting as an intermediary, "I always have this sense of, Don't negotiate, just take whatever they'll give us, because I'm just so scared that I won't be able to make a movie," she tells CNBC Make It. "I don't want to ask for too much."

For that reason, she's glad to have a middleman pushing for more than she might herself.

But Gerwig isn't alone in this fear of asking for too much. Only 38% of women feel comfortable negotiating for more money, while 56% of men are OK with it, a 2017 survey from Jobvite found.

And although women still do end up asking for raises just as much as men do, they're only successful 15% of the time, compared to men's 20%, researchers from the Harvard Business Review report.

For many women, a major factor for a successful negotiation is knowing what you're worth and asking to be paid a fair market value. Go into the discussion with hard facts about what your peers are earning and prove why you're an asset to the company.

But for Gerwig, directing movies comes with a much different pay structure than other professions. "Figuring out how you should be reimbursed for something and what you are worth is complicated," she says. How do you evaluate your value before you've even started the project?

More from Invest in You:
Greta Gerwig: Movies about women are 'not a bad investment'
This mother of five buys RVs online, flips and resells them—so far, she's made $22,000
Millennial who paid off $300,000 in debt in 3 years: How to live a frugal but still comfortable lifestyle

Part of the problem is a lack of transparency around pay, an issue that isn't unique to Hollywood, but certainly affects it. "On the one hand, everything is so public — you know how much a movie is grossing and you know roughly what the cost of making it was — but everything else is so hidden, like how much people are making or what their deals are," Gerwig says.

Eventually, she sees herself working toward a compensation structure that reflects how well her movies perform, she says, like the many established directors who choose to own part of their film in place of taking a salary upfront.

As Gerwig puts it, it's "a way to bet on yourself."

Like this story? Subscribe to CNBC Make It on YouTube!

Don't miss: Greta Gerwig: Movies about women are 'not a bad investment'

Greta Gerwig: Movies about women are 'not a bad investment'