FORTUNE — Michelle Lee, a tax partner at PwC in New York City, has a bucket list. She wants to visit 100 countries by the time she’s 60. So far, she’s taken vacations in 65 of them — including a journey to the Galapagos Islands and Machu Picchu, and a shark-diving expedition off the South African coast. This year’s plan: A week-long sojourn to Bali in November, complete with surfing lessons.
The best part is, she makes it a point to ignore her smartphone when she travels. “I’ve often deliberately picked locations with really bad cell reception,” says Lee. “I like to get far, far away, mentally as well as physically.”
Fewer and fewer of us, it seems, manage to do that. Consider: In 2012, 52% of employed Americans expected to work during their vacations, according to a survey of 1,094 full-time workers by online-meeting firm TeamViewer and Harris Interactive. This year, that figure climbed to 61%. Of those, about 40% said they’d be reading work-related emails, while 54% anticipated fielding texts and phone calls from the office. Some vacation.
Five years ago, top management at PwC decided that the firm’s 30,000 (now 37,000) employees would come back more refreshed and productive if they got away from work altogether. “We had had a particularly hectic fall, and there was concern that people would burn out if we went straight into our spring busy season without a break,” recalls Jennifer Allyn, a PwC managing director. “So, over the December holidays, we gave everyone 10 consecutive days off and encouraged them to unplug completely. Many employees told us it was the first work-free vacation they’d ever had.”
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The experiment was so effective at recharging people’s mental batteries that unplugged vacations have since become part of PwC’s culture. One reason it works is that entire teams and departments take off all at once, in between major projects, so that no one’s stuck back in the office trying to reach a colleague who’s sitting on a beach somewhere.
“It does take a lot of planning, and a lot of communication, in advance,” notes Michelle Lee, who manages about 40 direct reports. “But with some effort and practice, almost any team could probably do it.” She recommends these three steps:
1. Involve clients, including in-house customers, in scheduling time off. “With big clients, we write their time off, as well as our own planned vacations, into one big calendar that we send to everyone concerned,” says Lee. “That way, everyone knows ahead of time who will be available when.” She also sends reminders to clients, and other PwC employees involved in specific projects, before taking off to parts unknown: “People tend to forget when you’re leaving, so reminders give them a chance to raise any questions or concerns before you go.”
2. Anticipate problems that might come up and plan for them. “We sit down as a team and think through the details of different scenarios,” Lee says. “We talk about, ‘If this or that happens, who’s going to cover it? Whom can the client contact if we’re not here?’” Day-to-day tasks get delegated to another team, thoroughly briefed ahead of time, while senior-level decisions (if any) go to one of Lee’s fellow partners — for whom Lee and her team then cover when they take their own vacations.
3. If it doesn’t go smoothly the first time, try again. Making an unplugged vacation come off without a hitch “takes, frankly, a lot of work beforehand, and I didn’t always take the time to do it, so there were a few unforeseen problems in the beginning,” Lee admits. “But if there are some glitches early on, don’t give up on the idea of getting away for a real break. Just incorporate what you’ve learned into your plan for next year.”
One additional suggestion, from Jennifer Allyn: Remember that no one, in the end, is indispensable. The TeamViewer survey found that, although well over half of employees anticipated toiling away on their time off, only one in five (20%) said their bosses expected them to.
As Allyn, who is a fan of Harvard Business School prof Leslie Perlow’s book Sleeping with Your Smartphone, points out, “So much of the work people do on vacation is self-imposed. It takes self-discipline to put work completely out of your mind.” Later this month, Allyn is embarking on a four-week safari in Kenya and Tanzania. “I’m not bringing my phone,” she says, “so I won’t feel tempted to check it.”