Whether they've set a general return date or not, many law firms are still going to bring people back to their offices. But the cohort that comes in won't be the same as the one that left in early 2020.

Between new hires and departures and a new focus on maximizing in-office interactions, plus a new recognition of home-life stressors and the toll taken by a virus that's killed millions, firm leaders will have a new mix of employees on their hands, both literally and psychologically.

"I'm a real believer that coming back into the office is going to be almost as traumatic as leaving it 18 months ago. Because in the intervening months, people have gone through a hell of a lot of trauma and anxiety," Jim Jones, a senior fellow at the Georgetown Law Center on Ethics and the Legal Profession, said earlier this month.

"You've got a different group of people coming back. And the firms that are going to be the most successful will understand that and manage their people well."

That means laying new groundwork. Firms are of course making noise about things like wellness and stress-management, and that chorus was already growing louder before COVID-19 struck.

But even over the last year and a half, there has been "a chronic underestimation" in the legal industry of the effect the pandemic and increased workloads were having on lawyer mental health, burnout and dissatisfaction, said Randy Kiser, a legal profession scholar and principal analyst at DecisionSet.

It's also had a disproportionate impact on female lawyers and their role at law firms. An ABA study earlier this year cited pay, promotion and credit discrepancies, as well as isolation, long billing hours and unpredictable schedules, as among the top reasons why women ultimately leave the practice.

Several of those factors have been exacerbated in the wake of the COVID-19 outbreak, and despite concern about that issue, there has been a dearth of solutions, Kiser said.

"It's a good-faith, genuine concern. But it's not manifesting in many tangible steps," Kiser said. "I think firms might actually not know what it is they should be doing, and at this point it's more of a mystery to them than a business strategy."

Firms are also trying to imbue in-office work with new purpose, scheduling specific teams to be in the office at the same time.

It manifests in different combinations of people, with different, but perhaps more meaningful, mindsets.

"We've talked a lot about making sure teams come in and collaborate with each other, so people know when they come in, the people they want to see, their groups, are also going to be in the office," said Joe Krasovec, managing partner at Schiff Hardin.

"The concept is trying to bring people back with a purpose, so you don't have somebody who makes the commute, then realizes, 'I could've done the exact same thing from home.' I think that'll be a challenge, and part of getting used to the return. You're not just showing up everyday. It's not just a ritual. It's, 'OK, what am I doing today? Who is going to be there? What's the interaction, and how will that make it better?' "

Even some of the most basic things about bringing people together could be different. Paul Schmidt, of Baker & Hostetler, agreed there has to be " a value proposition" to bring people back in the office going forward, and for his firm, that involves people coming in on a rotational basis.

The firm pushed back its original Sept. 8 return date indefinitely. But before it hones in a new return date, Schmidt said he and other firm leaders are rethinking quite a bit—down to how their employees greet each other.

"There is going to be anxiety and sort of a hurdle, where people have to get back used to interactions," he said. "Little things, like do you shake hands? Fist bump? Keep your distance? There's an awkwardness to all of that that we need to also address and think about."

These leaders and others are making a bet—that the effort of bringing a fundamentally different group of people back to a more traditional way of working will be worth it in the long run, both for the employees themselves and the health of their organizations.

"It's OK to have some fun at work. There are bright spots—usually surrounding some interaction with your colleagues, and that can be formal or informal, but that's part of the experience of it," Schmidt said.

"Do you need that all the time? No. Are there benefits to having time with your children and being able to manage your life? Yeah, I see those benefits. But I also think there's real value to the in-person interaction that we're losing, and the glue and the culture. I think that you can rely on withdrawing from your culture banks for so long, but at some point, you've got to make some deposits in it."