Employers already know candidates are qualified for the job if they make it to the interview.

That’s why WeWork’s head of R&D, Josh Emig, asks an unconventional question during every interview that has nothing to do with qualifications. He wants to know what prospective employees do in their free time when they interview at WeWork, a communal work-space startup.

“I’m really intrigued by people who have diverse and varied backgrounds,” Emig says. “But what’s more important is their attitude and what they do outside of work — we’re looking for passionate people.” Employees with a “side hustle” tend to possess both openness and curiosity in the workplace, according to Emig.

Emig has hired a psychologist, writer, climate scientist and even a filmmaker.

“I love, for example, when people on my team are working on open source projects,” he says. “This is a good indicator of a person’s generosity and their skill.”

Take Joe Kachmar, who left his job as a rocket scientist at NASA to join WeWork’s R&D department this April. The move from NASA to WeWork might not seem like a natural transition, at least intuitively, Emig acknowledged to Yahoo Finance. But Emig knew Kachmar would make invaluable contributions to WeWork because of his passion for building and scaling products.

“The fact that Joe came from aerospace is great because he understand the electronics, engineering, hardware and software aspects of building things,” Emig says. But he was equally fascinated by what Kachmar did outside of the office.

At WeWork, Kachmar develops software and sensor hardware to help the company get a better idea of the perfect temperature, lighting, and density of people in designated spaces like conference rooms at each of their 115 office locations.

On the side, Kachmar has been working on a project that attaches two analog video cameras to a drone before it’s sent up in the air. This way, the video can be transmitted back to somebody on the ground and converted right away.

But Emig emphasizes that he’s not looking to integrate employees’ side projects into WeWork.

“It’s imperative that there is a separation between individual projects and what we’re working on as a team,” he says.

With the backdrop of a tightening labor market, it’s no surprise that employers are trying to find candidates who are well-rounded, versatile and possess perhaps some of the “soft skills” like critical thinking, communication skills and adaptability that were frequently overlooked in previous generations.

More than 53 million Americans — or one in three workers — are earning income from work that’s not a traditional 9-to-5 job, according to the US Bureau of Labor Statistics.

This strategy of taking interest in and embracing side gigs could be an optimal way for employers to retain talent. It might seem counterintuitive, but companies can help employees feel more fulfilled in the office by encouraging them to pursue passion projects outside of the office.

Melody Hahm is a writer & reporter at Yahoo Finance, covering entrepreneurship, innovation and technology. Follow her on Twitter.

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