In June 2017, Christopher Morris started work as an associate at Ernst & Young.

The 36-year-old is one of 14 people in the professional services firm's "neurodiversity" program, which hires people on the autism spectrum to work on its accounting and analytics projects.

Over the next three years, Ernst & Young plans to brings dozens more people like Morris on board.

"We need the talent wherever we can get it. Whichever way it's packaged. There is a shortage, particularly in our skills areas," said Lori Golden, who is leading the charge at EY to hire more people with disabilities.

It's not just Ernst & Young. With unemployment at a low 4.1%, fewer people are looking for jobs. As a result, many employers are having a hard time finding people qualified to fill the positions they have open.

That's left an opening for people with disabilities, a group that's broadly defined under the Americans With Disabilities Act. In addition to individuals with physical disabilities such as blindness, it also includes people who are struggling with addiction or have epilepsy, to name a few examples.

This demographic has always been underemployed. But Americans with disabilities have posted year-over-year gains in the job market for the past 21 consecutive months, according to an analysis by the Kessler Foundation and the University of New Hampshire.

"This is indicative of the economy reaching full employment, and employers reaching out to groups that they traditionally don't reach out to," said Andrew Houtenville, research director of the University of New Hampshire's Institute on Disability.

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Economic circumstances have helped speed up a broader cultural shift that's been underway since the ADA became law in 1990.

Since then, businesses have started to talk about diversity as a value-add. A growing number of firms include people with disabilities in that discussion, said Janet Bruckshen, executive director of Washington Vocational Services, which works to match individuals with disabilities with employers who are hiring.

Economists and advocates for people with disabilities say a Labor Department rule change under the Obama administration has also helped spur the change. In 2013, the agency issued a provision requiring all federal contractors try to fill 7% of their workforce with individuals with disabilities.

Bruckshen said her organization used to pitch businesses by telling them that hiring someone with a disability is the right thing to do. Now, the script has evolved.

"It's a business perspective. We go in and say retention is stronger for people with disabilities," Bruckshen said.

Golden said that Ernst & Young believes it can produce better work by giving people with disabilities a seat at the table.

"By bringing people in who think differently, you're bringing people in who look at problems differently," Golden said.

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For Morris, who works in Dallas, it's meant building a career. He said he intends to stay at EY for the long term.

"I majored in computer science in college and I've always wanted to work in the tech sector. I'm really excited that I have now the opportunity to develop that expertise," he said.

Technology has also made it easier for companies to channel changing attitudes into actual hiring. Remote work has become more common, and a greater number of processes are computerized in industries like manufacturing.

"Automation has taken away some of the barriers that may have prohibited someone with a physical disability from working in a steel mill," Mary Daly, executive vice president and director of research at the Federal Reserve Bank of San Francisco, said in an interview last week. A lot of heavy work can now be done with the push of a button, she said.

These factors have collectively created a more hospitable environment for people with disabilities looking for work.

Danny Goodisman, 43, was hired as a contractor at Boeing (BA) in August 2017 after spending two years looking for work in the Seattle area.

"Paying bills is less painful," said Goodisman, who has a rare degenerative disease that requires him to use a wheelchair. "Beyond that, a job is a big part of a person's identity. Now I can introduce myself as a programmer."

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That sentiment was echoed by Cooper Marx, a 25-year-old who lives in Arlington, Massachusetts. He's a brain tumor survivor who was hired at a local Whole Foods in October 2017.

Marx said the store lets him work four-hour shifts, which is the currently maximum amount of time he can stay on his feet.

"They were very willing to be accommodating," he said.

Despite these gains, the gap between employed people with disabilities and the general population remains sizable.

When looking at employment for people with disabilities, economists typically look at the proportion of the working age population with jobs, or the employment-to-population ratio, instead of the unemployment rate.

The employment-to-population ratio for working age people with disabilities hit 30.8% in December 2017. For working age people without disabilities, it was 73.3%.

But experts say the current job market could yield improvements.

"This is a moment," said Carol Glazer, president of the National Organization on Disability.