Immigration law refers to the national statutes, regulations, and legal precedents governing immigration into and deportation from a country. Strictly speaking, it is distinct from other matters such as naturalization and citizenship, although they are often conflated. Immigration laws vary around the world, as well as according to the social and political climate of the times, as acceptance of immigrants sways from the widely inclusive to the deeply nationalist and isolationist. Countries frequently maintain laws which regulate both the rights of entry and exit as well as internal rights, such as the duration of stay, freedom of movement, and the right to participate in commerce or government. National laws regarding the immigration of citizens of that country are regulated by international law. The United Nations' International Covenant on Civil and Political Rights mandates that all countries allow entry to their own citizens.

The Deferred Action for Childhood Arrivals (DACA) was an American immigration policy that allowed some individuals who entered the country as minors, and had either entered or remained in the country illegally, to receive a renewable two-year period of deferred action from deportation and to be eligible for a work permit. As of 2017, approximately 800,000 individuals—referred to as Dreamers after the DREAM Act bill—were enrolled in the program created by DACA. The policy was established by the Obama administration in June 2012 and rescinded by the Trump administration in September 2017.