Andrew Barnes is a fervent advocate for the four-day work week. And we might want to listen to him, because he knows what he’s talking about.

As the head of Perpetual Guardian, a New Zealand-based company that provides estate planning, philanthropy and investment advisory, Barnes did a trial run of the shortened schedule in March and April 2018. It was so successful that he adopted the policy full-time last November.

“We are all recognizing that how we work today is not fit for the 21st century, that the pressures of work-life balance are intense, and that the concept of how we work needs to change,” Barnes told Quartz at Work.

Most people may assume that the four-day work week is all about work-life balance and employee wellbeing, and it may well promote both. But, Barnes cautioned, that can’t be the emphasis when business owners decide to adopt the policy.

Instead, he said, the secret to successfully transitioning to a shorter work week is highlighting something else over wellbeing.

So what is it?

It turns out that, to not lose revenue and be happy with the transition, employers should focus on productivity when announcing the change to their workers.

“We sat down with each team and we said, ‘Right, let’s agree what is the base of productivity that you’re delivering now,’” Barnes told Quartz at Work. “And then the deal was, provided you delivered on the productivity goals, you would be gifted a day off a week.”

That gift could be revoked at any time if a team isn’t doing what they need to keep up their output. For some people, Quartz notes, that can mean increased stress, as “employees tend to police one another’s behavior.”

“It’s almost like a social contract with the team and the rest of the business,” Willem van der Steen, a manager at Perpetual Guardian, told Quartz. “You can’t really hide anymore.”

Productivity shines in a short work week

Still, the benefits are fairly indisputable. During Perpetual Guardian’s trial last spring, productivity went up by roughly 20%, while far more staff members felt they could “manage work and other commitments,” according to Quartz.

With the program in place for perpetuity, Barnes has set up a system where employees can opt in, but they don’t have to if it’s not their work style. Only about half of the company’s staff chose to take him up on the four-day work week, though he expects those numbers to continue to grow. Those who already went through the change have more time for family or additional training, they say.

For those in leadership positions who are interested in potentially trimming their work hours, Perpetual Guardian is releasing a paper on Feb. 19 with advice on how to move forward.

“We’re saying to companies all over the world: Just try this,” Barnes said. “What’s the worst that can happen? If you do a trial, your staff will love you for it, even if it fails.”

Originally published on Ladders.

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