NICOS, a surgeon in a regional hospital in Greece, is struggling with a painful decision. As Grexit has moved from a hypothetical scenario to an imminent threat, he and his wife have been staying up late into the night to mull over what they should do. “I don’t think we could stay,” says the father of two, who recently moved back to Greece after completing his medical training in Britain. He had hoped that his country was going to recover and wanted his children to grow up there. But recent months have been tough, with basic and medical supplies running low, as well job cuts. He is certain things will only get worse if Greece leaves the euro. All over the country, similar conversations are going on around the kitchen tables of doctors, lawyers, entrepreneurs, engineers and other professionals. Indeed, over the past five years (see chart) there has been an exodus of young, talented, highly-skilled Greeks to the shores of Britain, Germany, America and other rich countries. Around 180,000 Greek professionals (around 12% of people with graduate degrees) currently work abroad and many more study overseas. Some 130,000 Greeks graduates have left the country since the financial crisis, according to Lois Labrianidis, an academic who specialises in Greece’s braindrain.

The main reason has been a lack of knowledge-based jobs in Greece for the highly skilled. One of Greece’s hidden assets is its scientists: the country punches well above its weight globally. Some 3% of top scientists hail from Greece, which only accounts for 0.2% of the world’s population. But 85% of these research superstars live and work abroad, constituting a brain drain greater than that in any other euro-zone country.

The threat of Greece leaving the single currency, and possibly the European Union, has sparked a crisis of conscience for many of the highly-skilled Greeks who remain, and for those had recently returned, encouraged by signs of recovery. But Greece’s hotels and restaurants are full of overqualified engineers, lawyers and other professionals who have been waiting for things to get better. It is also preoccupying students looking for their first job. In Athens passport applications are said to have shot up in the past week as people prepare for their own Grexits.

John, a bright and energetic entrepreneur who speaks flawless English, came back to Greece in 2013 after finishing his studies in Britain because he wanted to “do something radical”. His start-up, a networking website for blue-collar jobs, is still at an early stage. But he has found the environment discouraging and the red tape burdensome. Out of his class at school only four pupils remain in the country, and two of them—himself and an architect with no work—are considering leaving.

For teachers, as so many other professionals, the situation is similarly bleak. Maria, a teacher by training, has yet to stand before a class of children. Instead she sells Vodafone sim cards on an Athens square in front of a slogan that reads: “power to you”.