Agriculture and the NHS are just two of the many businesses across Lincolnshire that rely on people from overseas - particularly on lower paid jobs.
But there are fears that tougher rules and regulations after Brexit could make it more difficult for some workers to remain in jobs.
There are also fears that it could deter others from coming to the UK.
Louis Harman, Head of Immigration at Chattertons Solicitors & Wealth Management, has spoken about the valuable contribution foreign nationals make to the county.
He says they are providing an ‘incredible contribution’ to the NHS and agricultural industry.
His advice to employers and employees is not to panic about post Brexit fears.
Mr Harman said: “I deal extensively with employers and employees entering the medical and agricultural sectors.
“The NHS and private medical practices in Lincolnshire rely heavily on foreign nationals to plug serious skill shortages here in the UK.
“I recently represented 10 to 15 specialists; doctors and consultants from Bangladesh, India, Egypt and Iran.
“They simply needed reassurance that their position in the UK was safe and protected.
“The level of contribution they provide is incredible.
“Without them the health care system simply wouldn’t function.
“The same can be said for the agricultural sector where we have been called out to businesses in Horncastle, Boston and Spalding to advise entire workforces of foreign nationals, mostly European, who need reassurance and clarity on their rights so that business can continue as usual.”
Mr Harman admitted that with Brexit looming, it was a ‘scary time’.
But he added proposed legislation - including visas or residence cards - would simplify the system.