  Immigration occurs when someone moves to another country in order to stay indefinitely. Thus, because of the brevity of their visits, tourists, business travelers and foreign students, for example, typically do not qualify as immigrants even though they spend time in a foreign country. There are a variety of important issues surrounding the morality of immigration, including difficult questions regarding the definition and moral status of refugees, the circumstances (if any) in which it is permissible to use guest workers, what obligations a rich country incurs when it actively recruits skilled workers from a poor state, the rights of irregular migrants, and whether there are any limitations on the selection criteria a country may use in deciding among applicants for immigration. This entry addresses each of these topics below, but first it reviews the most prominent arguments on both sides of the central debate in this area, whether states have the moral right to exclude potential immigrants.