RESEARCH TRIANGLE PARK, N.C. — Some information technology companies are growing so concerned about their inability to find enough digital talent that they’re training their own.

IBM, Amazon and Microsoft all now have apprenticeship programs that pay workers while they train for jobs demanding hard-to-find IT skills. Tech companies view apprenticeships — a staple of European labor for centuries and common in the U.S. for trades like welding and carpentry — as addressing the shortage of workers trained in skills that growing companies need.

It’s a problem that the U.S. Labor Department identified 20 years ago. And it persists even though the median pay last year for computer and information technology occupations was about $83,000, compared to $37,000 for all jobs, with demand growing rapidly over the next decade, the Bureau of Labor Statistics said.

IBM now has several hundred open jobs in the U.S. for people early in their IT careers — a number expected to grow over time — and is tackling the vacancies with its new apprenticeship program, vice president for talent Joanna Daly said.

“It’s not just IBM,” Daly said. “When you look at nationally, there’s a half-million open technology jobs in this country and we’re only producing 50,000 computer science graduates each year. So for the industry, we have a technology skills gap.”

IBM has long had apprenticeships at its operations in Germany, the United Kingdom and Australia, Daly said. The tech giant hired hundreds who’ve completed those apprenticeships, but hasn’t pinpointed if the program is mainly responsible for greater talent supply.

Industry coalitions as well as states like Minnesota and Washington have invested in encouraging IT apprenticeships. Trade groups including the Information Technology Industry Council and the Telecommunications Industry Association say more federal funding is needed. On Tuesday, President Donald Trump signed legislation increasing access to apprenticeship programs which train veterans.

But individual companies too are launching apprenticeship programs — a mix of classroom and paid on-the-job training to master skills.

Carousel Industries, which integrates and maintains communications and data networks, spends about $54,000, including salary, for each of the apprentices in its year-long program, Chief Client Officer Tim Hebert said Wednesday.

In the decade since Hebert started the apprenticeships at a company that Exeter, R.I.-based Carousel bought last year, 90 percent of the more than 320 workers who completed the program remain, he said.