ORLANDO, Fla. -- At the end of every work day, Siemens AG employees completely clean out their work areas in the company's new offices near the University of Central Florida. Desktops have no computers or phones. Drawers have no dusty human-resources manuals.

The German company's 300 employees are able to work in different parts of the office -- or even at home -- on any given day, depending on their needs.

The giant engineering company's new offices are one of seven Siemens locations in the United States that have adopted an "open concept" design. Taking advantage of an expiring lease, the company moved its work force from a 70,000-square-foot facility in the same east Orange County, Fla., research park to the new quarters, which consume about 55,000 square feet.

The open-concept approach is built on the theory that, at any given moment, only half of an office's employees are actually working in the office; the rest are out at appointments, in the field or taking time off. As a result, Siemens' new facility provides only 77 work stations for every 100 workers. And bosses generally don't get an office.

Branded by Siemens as NewWOW, short for "New Way of Working," the design allowed the company to trade the traditional office culture for added collaboration as it downsized its quarters. The open setting includes cafe areas, informal meeting spaces and "think tanks" for anyone who needs a bit of private space.

"It's the shift from 'me' to 'we,'" said Justin Mardex, strategy director for M. Arthur Gensler Jr. & Associates, the San Francisco-based architectural firm known simply as Gensler that oversaw the design work at Siemens' new Florida office. "It's a transition from being seen working to your work being seen."

Rooted in what is known as the "hotel concept," which let employees move among desks that were equipped with phones and laptop computers, this new style of office goes further by providing both computing power and phone service via portable laptops, plus lockers or storage space in which employees stash their belongings when they're not using them.

The idea, which appears to be growing in popularity, has its own set of buzz words, including "activity-based working," "workplace mobility" and "free-address approach."

A handful of companies shifted to this free-form office style about a decade ago, but more are now moving in that direction, having shed employees during the Great Recession. As companies start to grow again, Mardex said, they are looking for new office alternatives.

"A lot of times, it's driven by real estate and by an exercise in efficiency," Mardex said. "At Siemens, it's really a culture of change.