International migration is the movement of people across an international border involving a change of residence. The International Organization for Migration describes it broadly as movement across an international border, encompassing different durations, compositions and causes. International migration therefore includes people moving for employment, education, family reunification, business, humanitarian protection and other purposes. It can be temporary or permanent and can occur through regular or irregular channels. International migration is different from internal migration because an internationally recognised state boundary is crossed, although the social and economic processes underlying the movement can resemble those involved in internal migration.
International migration can be described from two complementary perspectives. The origin country experiences emigration, while the destination country experiences immigration. A migrant can therefore be simultaneously an emigrant from one country and an immigrant in another. Migration can also involve transit countries, multiple destinations and subsequent return. The international migration system is consequently not simply a collection of isolated movements between pairs of countries. Historical ties, labour markets, language, family networks, geographical proximity, colonial relationships, transport connections and migration policies can create persistent migration corridors connecting particular countries and regions.
International migration has many different drivers. Economic migration can occur when people seek employment, higher wages or improved economic opportunities. Education migration involves students who move to obtain qualifications or specialised training. Family migration occurs when people move to join spouses, parents, children or other relatives. Humanitarian migration can involve people seeking protection from persecution, conflict or serious threats. Environmental factors can influence migration where environmental change damages livelihoods or living conditions. These categories can overlap, and an individuals motivations can change during the migration process. IOM specifically recognises that migration can involve complex and mixed motivations rather than a single cause.
International migration is numerically significant but remains a minority experience at the global level. The IOM World Migration Report 2026 estimates approximately 304 million international migrants worldwide in mid 2024. The same source emphasises that most people still live in their countries of birth and that internal migration is considerably more common than international migration. International migration is therefore highly visible because it involves borders and immigration systems, but it should not be assumed that most people globally are international migrants. The global migrant population has grown over time, yet cross border movement remains a minority form of human mobility.
International migration affects both origin and destination populations. Destination countries may gain workers, students, consumers, entrepreneurs and family members, while origin countries may receive remittances, investment, knowledge and transnational connections. At the same time, migration can generate pressures involving housing, infrastructure, labour markets and public services in destination areas, while origin areas can experience population ageing, labour shortages or loss of specialised skills. The actual effects vary by scale, migrant characteristics, destination institutions, economic conditions and the duration of residence. It is therefore inaccurate to assume that international migration has one uniform effect on every country or community.
International migration is regulated through national laws and international frameworks. States generally control admission, residence and employment through visas, permits, border procedures and citizenship rules. Humanitarian protection creates additional legal obligations for particular categories of people, especially refugees. A refugee is not simply any international migrant who moves involuntarily. Refugee status has a specific legal meaning under international and regional refugee law, including protection for people who meet the applicable criteria and the principle that people should not be returned to places where they face specified serious risks. Asylum seekers are people who have sought international protection but whose claims have not yet been determined.
International migration statistics use several different measures. Migrant stock measures the number of international migrants residing in a country at a particular point in time, while migrant flow measures movements during a particular period. Foreign born population and foreign citizen population are also distinct measures. A person may be born abroad but hold the citizenship of the destination country, while another person may live in a country temporarily without being counted in a particular permanent migrant category. Statistical definitions also vary by duration of residence. These differences mean that numerical comparisons require careful attention to definitions, dates and data sources.
International migration is part of a larger system of human mobility involving travel, internal migration, commuting, tourism, displacement and repeated movement. Modern international migration has been transformed by faster transport, digital communication, global labour markets, international education and increasingly complex border regimes. The IOM World Migration Report treats international migrants, migrant workers, international students, refugees, asylum seekers and internally displaced people as related but distinct populations. Understanding international migration accurately therefore requires distinguishing ordinary migration from displacement and distinguishing broad demographic concepts from specific legal categories.
