This is a list of European Union member states, their forms of government and their parliaments. The European Union is a sui generis supranational union of democratic states. At a European Council Summit held in Copenhagen, Denmark, on 21 June and 22 June 1993, Form of government
See also: Self-governance
Most of the European Union's member states are unitary states, which means that most of the competences lie with the central government and only minor or local issues are within the authority of regional governments. However, three states are federations (Austria, Belgium and Germany) of states or regions with equal competences, and six other states have either devolved certain powers to special regions or are federacies (or both):

federacies:

• in Denmark, the Faroe Islands and Greenland are autonomous (and neither is part of the European Union);
  in Finland, Åland has substantial autonomy;
  in France, the collectivité sui generis New Caledonia (which is not part of the European Union) has a large degree of autonomy;
  in the Netherlands, the Caribbean island groups of Aruba and the Netherlands Antilles are equal partners to the Netherlands within the Kingdom of the Netherlands;
  in the United Kingdom, the Channel Islands — Guernsey and Jersey — and the Isle of Man are a special case, being neither part of the United Kingdom nor of the European Union; these islands are British Crown dependencies;
  devolved states:
  
  
  
  • in Spain, the central government has devolved various powers to the historic nationalities among the autonomous communities, namely Andalusia, the Basque Country, Catalonia and Galicia;
    in the United Kingdom, various competences have been devolved to the Home Nations of Northern Ireland, Scotland and Wales. The Greater London Authority also has extensive devolved powers. Degree of self-governance
    A further distinction is the number of chambers in the national legislature. While there had been legislatures with more than two chambers (tricameral and tetracameral ones), nowadays there are only unicameral and bicameral ones. There is no clear trend towards either model as of 2006, and there's also no real common factor which determines whether a country's legislature is unicameral or bicameral, except for the fact that federations and countries with strong regional differences or regional identities are normally bicameral to reflect the regions' interests in national bills.
    In the member states of the European Union, if the parliament has only one chamber, it is wholly directly elected in all cases. If there are two chambers, the lower house is directly elected in all cases, while the upper house can be directly elected (e.g. the Senate of Poland); or indirectly elected, for example, by regional legislatures (e.g. the Federal Council of Austria); or non-elected, but representing certain interest groups (e.g. the National Council of Slovenia); or non-elected (though by and large appointed by elected officials) as a remnant of a non-democratic political system in earlier times (as in the House of Lords in the United Kingdom).
    
    Houses of parliament
    
    Listed by type of parliament
    I^ : Due to Belgium's complex federal structure the Brussels Regional Parliament (Brussels Hoofdstedelijk Parlement / Parlement de la Région de Bruxelles-Capitale / Brüsseler Regionalparlament) (25, community assembly) have competences in federal legislation that affects their interests.
    II^ : In addition to the 71 elected senators, the ruling monarch's children (or, in case there are none, her or his siblings) are also entitled to sit in the Senate after reaching the age of 18 and entitled to vote after reaching the age of 21 as senators by law (senator van rechtswege / sénateur de droit / Senator von Rechts wegen), although they do not use the right to vote by constitutional convention. There are currently three such senators.
    III^ : The number of Senators will gradually increase to 341 in 2008 and 346 in 2011 to reflect changes in French demography.
    IV^ : While there is a Federal Assembly (Bundesversammlung) similar to the Austrian Federal Assembly, it is not simply a joint session of the Federal Diet and the Federal Council and as such not the overall name of the legislature.
    V^ : Technically, the Federal Diet only has 598 members; the additional sixteen seats are overhang seats.
    VI^ : In addition to the 315 elected members, there are currently seven senators for life (senatore a vita); these include three former Italian Presidents, who are ex officio senators for life, as well as four senators appointed by the President "for outstanding patriotic merits in the social, scientific, artistic or literary field". There can only be five appointed senators in addition to the ex officio ones at any one time.