The study looks at how being part of the European Union has affected Greece's immigration policies. Despite the belief that Europe is becoming more strict with immigration, Greece has actually made its policies more open over time. The researchers looked at Greek laws on letting in and keeping third-country nationals, comparing them across different parts of the government. They also compared these laws to rules on student immigration, ethnic immigration, and citizenship. The study found that Greece's immigration policies have been influenced by its own history and rules, rather than just following EU trends.