A foreign worker is a person who works in a country other than the one of which he or she is a citizen.
Citizenship is the status of a person recognized under the custom or law as being a legal member of a sovereign state.
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Migrant workers may follow work within their own country or between countries, depending on which definition is used.
The term "migrant worker" has different official meanings and connotations in different parts of the world.
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Some foreign workers are present temporarily and legally through a guest worker program in a country with more preferred job prospects than their home country.
A guest worker program allows foreign workers to temporarily reside and work in a host country until a next round of workers is readily available to switch.
Some are illegal aliens.
Illegal immigration is the migration of people across national borders in a way that violates the immigration laws of the destination country.
Foreign workers temporarily reside in the country in which they work, and will often send most or all wages earned back to their country of origin.