Last week’s Postdoc Conference and Career Fair for science and technology researchers had all the staples common at a recruiting event. Potential employers sat at folding tables, panelists discussed entrepreneurial endeavors and editors offered resume writing tips.

But unlike a job fair you might find in other industries, the nearly 500 attendees also had access to 20-minute consultations with immigration attorneys. Indeed, many in the crowd hail from countries other than the United States.

The national debate over immigration reform strikes a different tone in technology and science circles where demand for researchers and workers with specialized skills often has companies in need of more foreign nationals than can be hired.

“The first idea when you hear immigration is this whole idea of the border, Arizona, the fence,” said attorney Brendan Delaney of Bethesda-based law firm Leavy, Frank & Delaney. “But there’s a large population that U.S. businesses want and need here that are being ignored.”

A Brookings Institution report published earlier this month showed that the percentage of working-age immigrants in the United States, regardless of status, with a bachelor’s degree or higher has surpassed the percentage without a high school diploma.

But several attorneys whose entire practices center around immigration issues said that legal restrictions on visas have become tighter in recent years, making it more difficult for skilled workers to secure long-term stays here.

“Over the past couple of years, with the economy the way it has been, and the government putting more and more scrutiny on immigration . . . it’s gotten very, very difficult and I think it’s turned a lot of people away,” said John Nahajzer, managing shareholder at Maggio + Kattar.

The State Department issues different visas depending on an immigrant’s skill set and length of stay. J-1 visas allow for a short-term exchange but require recipients to return to their country of origin for at least two years unless granted an exception. Many of the fellows at last week’s conference have those visas, attorneys said.

H-1B visas allow employers to hire foreign workers with specialty skills. Attorneys said applications for those visas used to max out on the first day each year, but demand has slowed with the economic downturn.

The job market in many industries has taken a hit with the broader economic downturn, making it harder to find work. But technology, computer and engineering jobs have been among the most resilient.

“Unemployment in general almost never affects people in the very highly skilled jobs,” said Sheela Murthy, the head of Owings Mills-based Murthy Law. “If [companies] run an ad and say we have 10 openings, they’re lucky if they get five properly qualified people.”

Many of the life science and technology companies along Maryland’s Interstate 270 corridor rely on highly skilled workers, many of whom are foreign born, said Sally Sternbach, executive director at Rockville Economic Development. The authority organized last week’s career fair.

“I don’t understand why we’re not sophisticated enough in this country to differentiate between economic engines and the people we need to drive them,” she said. “They’re going to do the breakthrough diagnostics, the breakthrough devices, and I want them to do it here.”