Alien's passport

A certificate of identity, sometimes called an alien's passport, is a travel document issued by a country to non-citizens (also called aliens) residing within their borders who are stateless persons or otherwise unable to obtain a passport from their state of nationality (generally refugees). Some states also issue certificates of identity to their own citizens as a form of emergency passport or otherwise in lieu of a passport. The visa requirements of certificates of identity may be different to those of regular passports.

A certificate of identity issued to a refugee is also referred to as a 1951 Convention travel document (also known as a refugee travel document or a Geneva passport), in reference to the 1951 Convention Relating to the Status of Refugees. 145 countries are parties to the 1951 Convention and 146 countries are parties to the 1967 . Notably, the United States is not a party to the Convention, but provides travel documents to its lawful permanent residents, either as a Re-entry Permit or a refugee travel document under the 1967 Protocol.

A certificate of identity issued to a stateless person is also referred to as a 1954 Convention travel document, in reference to the 1954 Convention Relating to the Status of Stateless Persons. 89 countries are parties to the 1954 Convention.

Unlike a refugee travel document, a certificate of identity issued by most countries does not in itself entitle the holder to readmission into the country.

Non-Convention (or non-National) travel documents are travel documents issued by a country to non-citizen (also called alien) residents who do not have access to passport facilities from their own countries, are not recognized as either Convention refugees, and are not legally stateless under the 1954 Convention relating to the status of stateless persons (or the country they live in has not signed that convention).

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