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 Protocol Relating to the Status of Refugees. 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.