How would you like a four-day workweek? It may sound like a trick question, but it could become an increasingly common one as employers look for alternative ways to attract staff and boost productivity. Research from job search site FlexJobs suggests that a wide range of industries, from finance to recruitment, are opening up to the idea of a shorter workweek. Based on analysis of more than 50,000 U.S. companies' job postings, FlexJobs found that over the past year the following 10 industries were the most likely to hire for flexible positions, including those with four-day weeks: Sales

Computer & IT

Medical & health

Customer service

Education & training

Account/project manager

Administrative

Accounting & finance

Marketing

HR & recruitment Of course, the notion of a condensed workweek is nothing new. Fans of the four-day week have been espousing its benefits from a productivity and cost-cutting perspective since the 1970s. Indeed, in 1974, when the British government introduced a three-day workweek following an energy shortage, a national survey reported a 5 percent increase in productivity levels. However, with job disruption on the up and employees demanding greater flexibility at work, its scope is growing. A lifestyle that was once limited to a select few now "fits with more industries and jobs than you might imagine," Jim Link, chief human resources officer (North America) at global recruitment agency Randstad, told CNBC Make It. And it appears some employers are keen to make the shift.

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4-day weeks in action

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How viable is it?

While there's no cut and dried rule for how a four-day week would work, some suggest the most sensible option is to add an extra hour or two to each of the other workdays to compensate for lost time. According to FlexJobs' Rachel Jay, a career writer, that could be a "boon" for workers' productivity, providing them with "longer stretches of uninterrupted time to work." However, Adam Edwards, business director (Singapore) of global recruitment firm Hays, noted that "pressure on individuals to achieve the same output in four days as they have done previously in five could have a negative impact on stress levels." There are concerns about other negative implications, too. For instance, some have suggested a shorter workweek could hamper wages and potentially cause friction among professions that are less able to adapt, such as many manufacturing and medical roles. To manage those issues, Link said employers would have to think carefully about how they structure the work schedule and communicate that to staff. "The challenge is making sure productivity doesn't slip and that employees remain accountable to their bosses, customers, etc.," said Link. "As with any flexible work arrangement, misunderstandings are best avoided through regular, clear communication. Being upfront about expectations for employees with a four-day workweek — for example, is someone still 'on call' to respond to customer inquiries? — goes a long way toward keeping everything running smoothly," he added.

Making a 4-day week work