The U.S. labor market is already at what economists consider to be "full employment."
So for manufacturers and other businesses struggling to find qualified workers, one recent trend could be particularly disturbing.
The New York Times recently reported that the percentage of job applicants who tested positive for illegal drugs increased for two consecutive years after a decade of declines.
And, the paper noted, those numbers don't reflect the scale of the problem since prospective applicants often simply walk away once drug testing is mentioned.
In just one example, the Times said that several years ago — at a time of higher unemployment — about half of the attendees at a job fair for Savannah, Ga., equipment manufacturer JCB left prior to taking drug tests.
The issue is also particularly prevalent in the transportation and construction industries.
Drug testing is often required in the former sector for safety reasons, but the report also noted that states also reduce worker's compensation insurance costs for workplaces certified as drug-free.
Although marijuana was the primary culprit, the report also coincides with a dramatic rise in the use of heroin and other opiates.