'Right of abode' is a term that describes someone who is entirely free of any kind of immigration control. It applies to all British citizens (but not necessarily to other forms of British nationality). Irish citizens are treated as if they have the right of abode within the common travel area. Some citizens of Commonwealth countries also have the right of abode because they were born to a British parent or married a person with right of abode before 1 January 1983, and they can apply for a certificate of entitlement to prove their status.