The UN Declaration on Human Rights states that:

Everyone has the right to freedom of thought, conscience and religion; this right includes freedom to change his religion or belief, and freedom, either alone or in community with others and in public or private, to manifest his religion or belief in teaching, practice, worship and observance.

This definition of freedom of religion is used by the WEA Religious Liberty Commission in their statement of purpose.

Further information on the United Nations is also available.