Apprenticeship programs are growing as states realize that they’re facing “a wave of retirements”—but the new programs could help older workers retrain so they can keep working longer.

Alternatively, those programs could also ensure that there’s a ready crop of younger workers to choose from and lessen the possibility that an older worker can stay on the job past retirement.

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A PBS Newshour report says that as the federal government is encouraging apprenticeships, to the extent of providing funding for grants and tax credits to encourage private sector companies to offer them, some state agencies are taking heed and setting up their own programs, with paid training.

Older workers who see the handwriting on the wall in their current jobs or industries might want to investigate potential apprenticeship programs in various fields, particularly if they envision themselves working for years yet rather than leaving the job at retirement age.

But, conversely, those already on the job might find themselves watching their successors come up through the ranks as state agencies try to stay a step ahead of mass departures due to age.

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Virginia in particular is buying into the apprenticeship program in a big way. The report quotes Patricia Morrison, the division director at the Virginia Department of Labor who leads the state’s efforts to expand apprenticeships, saying, “It makes perfect sense for state agencies or county governments to utilize registered apprenticeships.”

She adds that the programs create a pipeline of younger, entry-level workers who will eventually replace retirees.

Across the country, according to the report, there are more than a half million apprentices registered with the federal government, but there  may be double that many employed in unregistered programs.

Registered programs, it adds, are obliged to meet standards, with apprentices who complete such programs receiving a journey worker credential recognized by both industry and the U.S. Department of Labor.

Thanks to differences in how states track and report enrollment in apprenticeship programs, there’s really no way to know the exact number of registered or unregistered apprentices who work for state and local governments. But police and fire departments often use apprenticeships to train new recruits, while some local governments use apprentices to train technicians, such as workers who maintain water treatment plants.

Other programs feed workers into a diverse range of professions, from nursing to vehicle maintenance to transportation operators and highway construction inspectors.

For the older worker looking for a new way to keep working in retirement, whether for pay or health care benefits, an apprenticeship could be the first step.