Should people have the right to move freely between countries? As it is well known, in large parts of the world, capital is already moving freely. And well-off people can move freely: in many developed countries, if you promise to invest enough, you get a permanent residence permit. But why limit this to well-off people? Why not let all people move as they want? It is a good question. But apart from the well-known problems in the country receiving the migrants, it is often overlooked that massive migrations carry high costs for the migrants. And the countries they leave behind tend to get stuck in a low level of development.