In the U.S., Shake Shack started testing the idea a year and a half ago. The burger chain shortened managers’ workweeks to four days at some stores and found that recruitment spiked, especially among women.

Shake Shack’s president, Tara Comonte, says the staff loved the perk: “Being able to take their kids to school a day a week, or one day less of having to pay for day care, for example.”

So the company recently expanded its trial to a third of its 164 U.S. stores. Offering that benefit required Shake Shack to find time savings elsewhere, so it switched to computer software to track supplies of ground beef, for example.

“It was a way to increase flexibility,” Comonte says of the shorter week. “Corporate environments have had flexible work policies for a while now. That’s not so easy to do in the restaurant business.”