The European Union (EU) is an international organisation which now consists of 28 countries with a population around 508 million people. I t is a very powerful organization, but it can only exercise as much power as the Member States give to it. The EU's Single Market is the most progressive trade co-operation, one of the greatest economic achievements and a key driver for the economic growth. It may be called like this, because of free movements of goods, persons, capital and services as well as eliminating tariffs, quotas and taxes on trade.The most protected group of persons under Article 45 (1) TFEU is workers, whose freedom of movement shall be secured within the Union. Their rights are more detailed in the Regulation 492/2011, which defines particular areas in which discrimination on the basis of nationality is forbidden. Among these are the access to employment, working conditions, social and tax benefits, housing, access to education for children.