EU citizens
EU citizens do not require a residence permit...
As EU citizens, all nationals of the Member States of the European Union have the right to move freely within the European Union and to enter and reside in any EU Member State. This right is guaranteed under Article 18 of the Treaty establishing the European Community. Basically, this right applies also to those family members of Union citizens who are nationals of a third country.
During the first three months of their stay, EU citizens who hold a valid travel passport or identity card, possess a right of residence without having to meet any further conditions. EU citizens do not require a residence permit.
Also, the right to the freedom of movement includes the possibility for EU citizens to take up an economic activity in any EU Member State, i. e. to take up salaried employment (citizens from the new EU Member States will be entitled to this right only after a transitional period) or to become self-employed or to provide services.
More information on EU citizens' freedom of movement and on EU enlargement is available here.