Countries which are not a member of the EU, the EEA or a contracting party to the EU are called third countries (also third-states). Switzerland can be considered a privileged third country. Owing to the Agreement on the Free Movement of Persons concluded between the EU and Switzerland, Swiss nationals enjoy similar rights of free movement as all other Union citizens. Andorra, Monaco, San Marino and the Vatican City are Euro countries but non-EU countries and therefore third countries.
A differentiation is made between positive and negative third countries: citizens from positive countries are allowed to enter the Schengen area without a visa for up to three months. Nationals of negative third countries require a valid visa to enter.