Want to close the gender wage gap? Stop telling women to lean in and start encouraging dads to lean out.

For the seventh year in a row, tiny Iceland led the world in gender parity, according to the World Economic Forum’s annual Global Gender Gap Index. That doesn’t make Iceland a feminist utopia by any stretch of the imagination, but it does mean that the country is getting a few key things right. The report ranks 145 countries on the gap between women and men on health, education, economic, and political indicators, and Iceland came out on top.

And where, might you ask, does the United States rank? Twenty-eighth, which is the lowest it’s placed since 2009.

So what makes Iceland different? Some major structural incentives to promote gender equality, for one thing.

Iceland, like the other three Nordic countries at the top of the index, offers generous maternity and paternity leave to new parents. In Iceland, mothers and fathers are each given three months of leave at 80% pay and three months that they can share as they see fit. (A plan to extend leave to five months for each parent and two months of shared time was passed in 2012, but has yet to be implemented.)

But instead of just offering paternity leave, the policy is structured so that the time allotted to fathers isn’t transferable. The use-it-or-lose-it nature of the program is coercive by design: As Catherine Rampell put it in a piece on paid leave for The New York Times, any time left unused is money left on the table.

As it turns out, subtle manipulation works when it comes to keeping dads home with their kids. According to a 2014 report from U.N. Women on gender parity in Iceland, 90% of dads in the country took leave in 2012.

A recent body of research suggests that the incentives that help keep dads at home in the first years of a child’s life can have long-term benefits beyond just allowing them to spend quality time with their kid without worrying that it will cause their family will go broke.

Having a dad at home early on also kind of resets gendered expectations around work-life balance, as Rampell pointed out in the same Times piece:

A striking new study by a Cornell graduate student, Ankita Patnaik, based on a new paid paternity-leave quota in Quebec, found that parents’ time use changed significantly. Several years after being exposed to the reform, fathers spent more time in child care and domestic work—particularly “time-inflexible” chores, like cooking, that cut into working hours—than fathers who weren’t exposed to the reform. More important, mothers spent considerably more time at work growing their careers and contributing more to the economy, all without any public mandates or shaming.

Keeping dads home may also help to close the gender wage gap. Sweden, which is fourth on the global index, has a similar use-it-or-use-it policy in place to incentivize paternity leave. And according to a study published in 2010 by the Swedish Institute of Labor Market Policy Evaluation, a woman’s future earnings increased an average of 7% for every month of paternity leave her partner used.

Part of it is the simple fact that, in a straight, two-parent household, when dads take on more responsibilities at home, moms are freed up to do other stuff, like return to the workforce earlier or put in later hours.

But it’s also about shouldering burdens more equitably. Incentivizing paternity leave can “spread the stigma around so that women don’t get singled out for being the potential problem hires or problem employees,” according to Liza Mundy, the former director of the Breadwinning & Caregiving Program at New America.

“If everybody—male or female—is asking for leave or taking leave that they already qualify for,” Mundy explained in an interview with Fast Company, “I think it just levels the playing field for how men or women are looked at in the office.”

This makes a lot of sense if you think about it.

As it stands in the U.S. right now—virtually the only advanced economy in the world that doesn’t offer some form of paid parental leave—women disproportionately shoulder their family’s childcare and other domestic needs.

Women being pulled away from work or forced to work a double shift because of the needs of their family is part of what feeds the mommy track. But sexist bias—implicit and explicit—feeds it, too. As a small recent study found, just the perception that women need more flexibility to accommodate their work-life balance can stigmatize women and hurt their standing at their jobs.

Erin Reid, a professor at Boston University’s Questrom School of Business, interviewed 115 employees at an elite consulting firm with a culture of “working long hours and traveling constantly” to see how people coped with the demands of the job.

Reid found that men and women both reported feeling stressed by the expectation that their work should take precedence over every other aspect of their lives. They just tended to deal with it differently.

“My research revealed that men were just as likely as women to have trouble with these ‘always on’ expectations,” Reid wrote in The Harvard Business Review. “However, men often coped with these demands in ways that differed strikingly.”

According to Reid’s research, women who needed more flexibility were more likely to use “formal accommodations”—asking for flextime, scaling back hours—whereas men at the firm found “under-the-radar ways” to balance their hours. They cultivated local clients and formed alliances with other colleagues so that they created the impression of working longer hours, even if they weren’t.

Women at the firm were often marginalized for using the formal accommodations, but the men who were able to “pass” as what Reid termed “ideal workers” while still limiting their hours were championed within the firm.

Reid attributed the difference to a few things, but one of them was a gendered expectation about how men and women use their time. Based on her interviews with employees, Reid found that people at the firm assumed women who left the office by 5 p.m. were going home to take care of their kids, while they assumed men leaving at the same time were heading out to meet a client.

This penalty for women might not disappear entirely in a culture where men and women share domestic responsibilities more equitably. (Iceland gets a lot right, but inequalities still persist there, according to the Global Gender Gap Index.) However, making structural changes to the workplace is a pretty good place to start—particularly in the United States, where fewer than 15% of workers have any access to paid family leave.

The Icelandic model may not be perfect, but the data—and basic common sense—suggest that strong structural supports that help parents balance their work and home lives are a hell of a lot more useful than just telling women to lean in.