Especially in the United States, Canada, and Europe, there are more jobs. So the poor people move to these countries to look for work. They may leave their homes and families only for a few months or years. That is what some people from Romania and Ukraine do in Italy and Germany. But many other people never return home. They decide to stay in their new country, and they become immigrants. That is what happens in the United States for many workers from Mexico and Central America.