A refugee is a person who has left their country and cannot or will not return due to fear of persecution. This persecution must be based on race, religion, nationality, political opinion, or membership in a particular social group. To be considered a refugee, the person must not be firmly resettled in another country.

Refugees hoping to resettle in the US must first be referred to the US Refugee Admissions Program. Only after being referred can a person outside the country complete their application for refugee status.

Other countries outside the US have refugee resettlement programs. These are based on the 1951 Refugee Convention and 1967 Protocol, which established international laws concerning refugees.

The main difference between immigrants and refugees is that immigrants choose to leave their home countries voluntarily while refugees are forced to do so because of persecution. While immigrants can typically return home safely, refugees cannot or will not.

Refugees and asylum seekers differ only in whether or not the person is already in the US. To receive refugee status, an applicant must be located outside the US; an asylum seeker meets the definition of refugee, except that they must already be inside the US.