The free movement of workers is one of the four freedoms of the EU Internal Market. Migrant workers who move from one state into another enjoy certain rights stipulated by the EU Law (acquis communautaire). The aim of this article is to make a comparison between the rights enjoyed by the workers from EU member states and third country workers, in particular from Turkey and the Republic of Macedonia. This paper examines the possible effect of the enlargement of the European Union on Western Balkan countries and Turkey with respect to the freedom of movement of workers in the context of the impact of previous EC enlargements on migratory movements.