Over the summer, Zillow Group joined a swarm of companies telling employees they would never have to return to their offices on a regular basis. This marked a reversal for the online home-buying firm, which had leased some of Seattle’s most expensive real estate and added amenities like air hockey and pingpong. But after a few weeks working remotely in the early phase of the pandemic, most employees said they were happier working at home.

This week, Zillow CEO Rich Barton and his lieutenants took on a more complicated task—explaining to the company’s 5,500 employees how it will implement the new policy after the pandemic wanes, when about 35% of Zillow’s staff are expected to work from offices at least occasionally. In doing so, Barton, like other tech CEOs, must grapple with competing employee and business needs, with little visibility into what works best.

Many employees at Zillow and other companies don’t want to return to a Monday-to-Friday office commute. Yet managers know remote work can make it harder for employees to collaborate and, especially for working parents, get their jobs done.