Although most of the world's 196 countries have joined forces to tackle global issues like global warming, trade policy, and human rights and humanitarian issues through joined the United Nations as members, three countries are not members of the U.N.: Kosovo, Palestine, and Vatican City.
All three, however, are considered Non-member States of the United Nations and have therefore received standing invitations to participate as observers of the General Assembly and are provided free access to documents of the United Nations.
Although not specifically dictated in provisions of the United Nations, the non-member permanent observer status has been recognized as a matter of practice in the U.N. since 1946 when the Swiss Government was given the status by the Secretary-General.
More often than not, permanent observers later join the United Nations as full members when their independence has been recognized by more members and their governments and economy have stabilized enough to be able to provide financial, military or humanitarian support for international initiatives of the United Nations.