What’s the secret to a happier office: iced coffee on tap, hot-desking, bike rooms, personal phone booths, a ping pong table? Businesses across all industries are rethinking the office by deploying flexible configurations or providing amenity-rich spaces to motivate teams and drive productivity, but the key to employee engagement is something you can’t physically see or touch when you look around the office.

Driving employee engagement has been at the forefront of effective management for decades, but now more than ever, it is central to employee attraction and retention. For today’s workforce, an engaging work environment is an expectation for new hires and an ineffective office environment has the potential to drive away your most valuable talent.

At a recent WiredScore panel on the future office, a workplace building manager from Uber shared a hurdle that their company has encountered during its rapid expansion. To accommodate tight launch deadlines, new offices across different markets were opened without a permanent furniture solution in place. The strategist noted, however, that if the new space doesn’t have internet connectivity, the office cannot open for business.

Adobe’s 2016 Future of Work Report found that 81% of office workers say that state-of-the-art technology was more important to them than an office’s design or on-site amenities. If there is one thing that today’s workers absolutely refuse to put up with, it’s issues with their internet connection. Adobe’s study also found that those U.S. workers who said their company’s technology is “ahead of the curve” feel roughly twice as creative, motivated and valued and love their work about twice as much compared to those at companies whose technology is “behind the times.” The Value of Connectivity, a survey conducted by Radius Global Market Research in partnership with WiredScore found that when connectivity issues occur, companies report increased employee stress (45%), frustration in helping customers (41%) and lower productivity overall (36%).

In some ways, good connectivity affords your employees the ability to connect better on a personal level, through face-to-face or audio interaction. Though positive in some regards, high mobility and flexibility can run the risk of pigeonholing personal interaction to platforms like Slack or Chrome but it also increases the chance for people to connect more closely through different media, such as high-quality audio and video. Video in its most clear, uninterrupted form is vital to people actually feeling connected with their co-workers and leadership, thus increasing the likelihood of a positive, healthy work environment.

An internet outage, especially one of an indeterminate length of time, shuts down all that useful technology and is guaranteed to grind business to a halt. The result? Upheaval in the workplace and lost profits until it is restored. If you are a business owner looking for new office space, make sure to ask your broker for comprehensive information about the quality of internet connectivity in the building.

It’s not just your company’s profitability that’s at stake; it’s your employees’ happiness, too. Because of this, you need to look for certain infrastructural elements to ensure that a potential office space is up to snuff. To find out if a building is fully equipped for connectivity, you should ask about a building’s number of internet service providers (ISPs), whether they have access to any backup connections and the protections put in place to secure telecom equipment from accidental damage.