Note to executives: Your employees are in the dark

FORTUNE — If your business depends on an army of delivery drivers, cooks, and waitpersons, retail sales staffers, field technicians, or other employees who move around all day, here’s something that may surprise you: Most of them wish you would talk to them more.

So says a new survey of “non-desk” workers at U.S. companies with more than 1,000 employees. An 84% majority said they don’t get enough information from top management, while 75% said their employers aren’t telling them enough about changes in policies and goals. Almost the same number (74%) said “consistent” messages from senior management, although few and far between, are important to them.

Two clues as to why these workers feel left in the dark: 83% are not on their companies’ email systems — although more than one-third (38%) say they would like to be — so they’re not getting the memo that way; and 73% say they rely instead on their immediate supervisors to keep them informed.

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“Counting on people’s immediate bosses to keep them up-to-date sounds fine in theory, but it doesn’t work,” says Elizabeth Cogswell Baskin. “For one thing, some supervisors are better communicators than others, so important messages can get lost in translation. There’s also a frequent problem with inconsistency in timing. Some employees get the word about big changes before others do, simply because some bosses haven’t told their people yet.”

Baskin is CEO of Atlanta-based communication consulting firm Tribe Inc., which has worked with Home Depot (HD), Coca-Cola (KO), Target (TGT), Porsche of North America, and other big outfits. If it seems self-serving for a communications company to recommend (surprise!) better communication, well, maybe so. Still, the poll results are worth pondering. Tribe embarked on the project because Baskin noticed in meetings with corporate executives that “over and over again, they’d say to me, ‘’Just work with the people at headquarters. It’s too hard to reach the people who are out in the field,’” Baskin says.

“That creates a huge gap,” she observes. “To customers, front-line employees are the face of the company. You can spend millions building a brand through advertising and marketing, but a few bad customer experiences are enough to blow it — especially if they go viral.”

So how do you reach those legions of workers who want to hear more directly from the top? Since most (86%) of those surveyed spend time online at home, “you can leverage communication channels your employees already use, like Twitter,” Baskin notes. “Company intranet sites are also a really effective tool.” Among employees with access to an intranet site, the survey found, 43% say it helps them do their jobs better.

UPS (UPS) has raised employee communication to an art form, according to Baskin. Supervisors there “talk to their teams, but the company also has a great intranet site,” she says. “They also publish a magazine they mail to employees’ homes, and they are constantly tweeting, whether it’s to congratulate a driver on an anniversary with the company or to give news like, ‘We just delivered an elephant to the San Diego Zoo.’

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“The more different ways you can find to reach out to your people in the field, the more likely it is that they’ll get the information you’re trying to convey,” she adds.

Of course, that doesn’t mean they’ll always like what they hear. A sizable group (43%) of employees told Tribe’s researchers that they don’t know their company’s vision for growth. Among those who did, some made comments like this one: “Unfortunately, the vision is totally different from my view.”

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