The economy is sputtering, and companies say they will make nothing but perfect-10 hires. Meanwhile, Baby Boomers are retiring by the millions -- and everyone wants to be a millionaire, not a wage earner. Where does all this leave employers and workers in their never-ending struggle to tip the balance in the American labor market?

From the perspective of an annual survey commissioned by staffing firm Manpower, these dynamics yield a number of occupations for which openings are hard to fill. Among white-collar jobs, the following positions make Manpower’s 10 Hardest Jobs to Fill list: sales reps, nurses, technicians, restaurant/hotel workers, managers/executives, doctors/other clinical practitioners, engineers and customer service reps. And on the blue-collar side, skilled tradespeople and drivers make the top 10.

But labor-market power has shifted toward employers with the soft economy. In the prerecession year of 2007, Manpower’s survey of 2,000 US firms showed that 41 percent of employers reported difficulties filling positions; however, the 2010 tally found only about a third of that percentage of companies -- 14 percent -- reported recruitment was a struggle.

And many experts, especially labor advocates, take issue with the Manpower study’s conclusion that all these occupations are in shortage. “Our starting point at EPI is where most economists would start: If you don’t have low unemployment and rising wages, you don’t have a shortage,” says Ross Eisenbrey, vice president of the Economic Policy Institute (EPI).

So if you work in one of these occupations -- or want to -- what’s the real story? Let’s take a look at the survey results and get some perspective on what the shortages really mean.

White-Collar Occupations Blow in the Winds of Economic Change

With fuel prices spiking and oil and natural gas exploration heating up, demand for petroleum engineers is rising. Offshoring notwithstanding, “engineering is going to be around for awhile,” says Melanie Holmes, a vice president at Manpower North America. “Oil companies have employees averaging in their late 40s.”

Eisenbrey says EPI data shows labor shortages in a number of white-collar niches, from healthcare workers to librarians, farm managers, engineering managers and environmental scientists.

Some Blue-Collar Jobs Go Unfilled Even as Their Numbers Drop

Even after decades of manufacturing decline, employment of machinists is expected to drop another 5 percent between 2008 and 2018, according to the BLS.

“We’re at the very beginning of that decline; we haven’t necessarily gotten there yet,” says Holmes. “Even if machinists are declining, applicants are in short supply. Kids are not getting excited about going to tech and vocational schools.”

Labor advocates paint a different picture. “Employers are still not willing to pay what’s required,” says Eisenbrey. “It’s a shortage only at the rate that employers want to pay.”

The skilled trades rank high among blue-collar jobs that are hard to fill, according to the Manpower survey. Carpenters, welders, plumbers, electricians and masons are in demand, the survey says.

But Eisenbrey questions the validity of these conclusions. “It doesn’t make sense that jobs for construction workers and laborers are hard to fill,” he says. “Wages are declining in most of these occupations." While the Associated General Contractors of America reports that 40,000 new construction jobs -- many due to stimulus projects -- were added between February and April 2010, that's a far cry from the more than 2 million construction jobs lost over the previous three years.

Even in our digital age, stuff still needs to get from here to there, whether the trip is across the warehouse floor or around the world. That’s why jobs for laborers such as freight, stock and materials handlers are projected to increase by almost 250,000 positions from 2004 to 2014, according to the BLS. Many of these jobs require few skills but pay $12 to $15 an hour, about double the federal minimum wage, which rose to $7.25 per hour on July 24, 2009.