Why go to the mall when you can shop at work?

Working and shopping have traditionally meant two separate activities. Now, thanks to the Internet, employees can shop till they drop without ever leaving their desks.

With a few clicks of a mouse – keeping one eye on the electronic order form, the other on the boss – workers are checking holiday gifts off their lists. That leaves managers pondering a sticky question: How much e-commerce – if any – is permissible on the job?

"This time of year, it's the greatest abuse of online activities," says Jennifer Berman, managing director of CBIZ Human Capital Services in Chicago. "A lot of employers do try to be reasonable. They understand people are strapped for time."

Nearly one-third of workers use their computers at work to shop online, according to a new Spherion survey conducted by Harris Interactive. Many are also shopping faster. Nearly half spend less than 15 minutes each time they make a seasonal purchase at work. Those between the ages of 25 and 29 are most likely to be cyberbuyers on the job.

As one measure of the popularity of workplace shopping, on "Cyber Monday" after Thanksgiving, 32.5 million buyers spent a record $733 million shopping online. Sixty percent of the money they spent flowed from workplace computers.

That day Bill Wiseley, a partner at Ready to Hire, an online staffing service in Willow Grove, Pa., even brought in lunch for his 25 employees so they could spend their full lunch hour shopping. He places online shopping in a category with personal phone calls and personal e-mail.

"As long as it's within our established boundaries, we have no problem with it," Mr. Wiseley says. "We really feel our employees are giving 110 percent. We're not averse to 15 minutes a day for a few days [during the holidays] to do some online shopping. Then their mind-set will be fully dedicated to their workload."

Yet more than half of human-resources professionals have had to discipline their staff for wasting time on the Internet, according to a survey by Clearswift, a high-tech security company headquartered in Redwood City, Calif. Although nearly 90 percent of these companies say they have a written policy on Internet use, far fewer have ways to enforce the policy.

Wiseley, who maintains ethical and professional guidelines for Internet use, relies on security tools to monitor all Internet activity. "I get reports weekly about our employees' Web activity," he says.

One owner of a public-relations firm in the Northwest learned the hard way about the importance of having an Internet policy. Last week, she discovered that her assistant frequently shops online. She also spends time on MySpace and other social-networking sites, as well as on video games and music sites.

"I feel rather devastated," says the owner, who requested anonymity because she has not yet confronted her employee. "I was grooming her for a great position. Now I don't know what to do."

Her discovery came when the firm that monitors her computers for viruses noticed significant online activity and notified her.

"She's 24, and I understand that she's grown up with this," the woman says. "But it's hard to believe she doesn't realize this is not an appropriate thing to do when she's on someone's payroll. I know people take little breaks during the day – we all do that. You can't think about work 100 percent of the time. But how can you be focused on work when you're registered in these accounts?"

Some workplace shoppers turn into artful dodgers, cleverly hiding their online activities. "If the boss walks in or they sense somebody is behind them, they press a key, and it looks like they've got an Excel spreadsheet up," Ms. Berman says.

Certain companies must prohibit all nonbusiness use of the Internet, says Philip Gordon, an attorney at Littler Mendelson in Denver who specializes in workplace privacy. But for most others, he suggests that it may be better for employees to spend 15 minutes online than to run out on Dec. 21 because they haven't finished shopping and disappear for two hours.

He advises employers to set limits on the use of non-business resources. Make it clear to employees that nonbusiness use is not private, is subject to company policies, and should be limited to breaks, lunch hours, and short periods before or after work hours.

Brian Olson, a vice president at Video Professor, a provider of computer software tutorials in Lakewood, Colo., has bought a few items online at work, but only on his lunch hour. "Twenty-five years ago people were writing about spending too much time around the office water cooler," he says. "This is just what's replaced it. It appears the American worker is especially good at shopping and being productive at the same time."

Claire Simmers, coauthor of "The Internet and Workplace Transformation," sees the need for a shift in corporate attitudes. "We've got to get away from basing our performance on those eight hours," says Ms. Simmers, an associate professor of management at St. Joseph's University in Philadelphia. "We should be thinking about outcomes. If I spend an hour surfing the Net but I've spent the whole weekend working on a report, there should be trust that we're both equally benefiting from this relationship. We're still assuming that we have to take very tight control of what happens in the workplace, almost as if the employers are the parents and the employees are the children, rather than us being co-equals in this partnership to advance the company."

When Laura Stack, a workplace productivity specialist, conducts time-management seminars, she finds that most companies don't mind limited amounts of shopping online as long as employees do it on personal time and do not abuse the privilege.

"The time is more than offset by the number of hours workers are clocking from home and on personal time, such as checking their Blackberrys while watching Little League games," says Ms. Stack of Highlands Ranch, Colo. "The boost that an organization will get from higher morale with a bit of leniency on online shopping will more than compensate for lost time. If a manager observes excessiveness, limits may be called for. But in general, employees can be trusted until proven otherwise."