They work in careers as varied as programming, illustration, and food service.

But they have one thing in common: They aren’t working full-time, but instead picking up contract work piecemeal.

Temporary workers haven’t taken over the workforce, but in recent years, they’ve become a more significant part of it—partly due to the economic downturn.

“We argued when the recovery began that there would be a structural shift,” American Staffing Association COO Steve Berchem told NBC News. “We were hearing that from members who were hearing that from their clients, (that) they were more likely to use temp and contract workers.”

Berchem emphasized that individual months should not be looked at for long-term context, but he also noted that in March, temporary work topped more than 2 percent of the workforce—a peak not seen since April 2000.

Some people don’t want to be a full-time employee. They want contract work.

Economists’ Concerns

While temporary work generally rises in the wake of a recession, economists believe there may be evidence that the rise can cause long-term issues, as such employees are less likely to spend their paychecks than are full-time workers, partly due to the lack of job security. And while efforts to organize workers who aren’t full-time are growing, many of these workers aren’t unionized.

“Workers increasingly serve businesses that do not officially ’employ’ the worker—a distinction that hampers organizing, erodes labor standards, and dilutes accountability,” the National Employment Law Project’s General Counsel Catherine Ruckelshaus told The Associated Press.

That has many economists worried about the long-term results, especially as these employees are often easier to release than are full-time workers.

“In the private sector there’s no counterbalancing power,” the Center for Economic Policy and Research’s Eileen Appelbaum argued to NBC News. “The decisions are almost costless to them.”

Defending the Practice

The expansion of contract work nonetheless draws differing opinions from trade groups, which note that there are benefits to contract or temporary work that can’t be had with full-time work, such as additional flexibility. (For full-time workers, such flexibility is often harder to come by.)

“Some people don’t want to be a full-time employee. They want contract work,” the U.S. Chamber of Commerce’s executive vice president, Bruce Josten, said to the AP, though he noted that many contract workers are often looking for full-time work—something spoken to by Bureau of Labor Statistics reports.

Some industries, such as manufacturing, lean particularly heavily on contract workers, with one estimate from the W.E. Upjohn Institute for Employment Research stating that manufacturing companies hire around 40 percent of all contract workers. Manufacturing industry figures say there’s more bad than good about such setups.

“I think on balance, they are a positive reflection of the extent to which production has become much more flexible, a reflection of hybrid operations,” Jerry Jasinowski, the former head of both the National Association of Manufacturers and the Manufacturing Institute, said in comments to the AP. “Some people don’t like it. But that’s neither here nor there. That’s where everybody’s moving.”

For associations, is there an opportunity to reach a new audience by offering services to temporary workers? Offer up your take in the comments.

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