Supervisors in industries like construction and office cleaning have grappled with it for ages: How do you best manage offsite employees when they’re out of your sight — and in many ways, out of your control?

These days, an increasing number of employers with telecommuting workers share that challenge. The number of those regularly working from home (but not self-employed) has grown 103 percent since 2005, reports Global Workplace Analytics.

As such, employers have had to find new methods for monitoring worker productivity. Their biggest challenge is a lack of face-to-face communication, according to 30 percent of chief information officers surveyed last year by Robert Half Technology. Another 22 percent pointed to technological challenges.

If you are coping with similar issues, consider these five tips:

1) Provide the technology and network access for speedy, convenient communications, advises John Reed of Robert Half. Then establish clear expectations and guidelines for regular (as well as spur-of-the-moment) conversations. Buddy Punch can automatically gather GPS coordinates, snap photographs and send email advisories to supervisors every time employees punch in or out.

3) Ensure both off-site workers and your IT department understand cybersecurity issues, advises Paul McDonald on CPApracticeadvisor.com. This is especially important since employees will be reliant on mobile apps as well as external servers and equipment.

4) Make remote workers feel like part of the team via regular feedback and praise, and include them in training and company-wide events, stresses Matt Krumrie on Flexjobs.com. By the same token, don’t expect them to jump through hoops not required of on-site workers, like answering emails after hours.

5) Don’t miss warning signs that the employee might be unproductive, advises McDonald. Red flags include arriving late or not showing up for phone or video conferences, taking longer than usual to respond to emails, texts or phone calls, missing deadlines and turning in sloppy work.

One challenge you may not have thought of? Off-siters as workaholics.

“Because the manager isn’t sitting across from her worker anymore, she can’t look in the person’s eyes and see burnout,” speculates Jason Fried on Inc.com.