A situation in which the workers in a country are unable to form and join trade union organizations of their own choosing for the protection of their interests, is contrary to generally recognized principles relating to freedom of association. Sometimes freedom of association is denied on the basis of occupation, sex, colour, race, beliefs, nationality, political opinion, etc, not only to workers in the private sector of the economy but also to civil servants and employees of public services in general. Even if freedom to establish trade unions has long been recognized in a great many countries, authorization to establish associations is not in itself sufficient to guarantee their effective development, due to restrictions such as single trade unions, government favouritism of a trade union, or compulsory union membership.