Undoubtedly, professional football hails as the most popular sport around the world. Dozens of football players, coaches, managers, agents, and fans are partake in it every day in some form, whether it is earning money, entertaining, or simply watching this sport. However, a crucial issue that requires attention is the immigration of players to foreign championships in order to be able to take advantage of professional opportunities or to find a way into more advanced football leagues. The purpose of this book is to study the immigration of athletes onto the European football field, with an emphasis on the Greece Superleague. The main conclusion that has emerged from this study is that more and more Greek players take advantage of the free market and choose to leave by migrating to find better working conditions in one of the most advanced European championships. At the same time, this book addresses that the flow of foreign athletes has increased remarkably in all European countries and in Greece specifically, which is the seventh highest host European country of migrant footballers, despite the small size and competitiveness of the Greek league.