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The country's constitution was revised on 14 July 1993 to create a unique federal state, with several governmental entities based on three levels.

The federal government, based in Brussels.
The three language communities:
the Flemish (i.e., Dutch-speaking) Community;
the French (i.e., French-speaking) Community; and
the German-speaking Community.
The three regions (which differ from the language communities with respect to the German-speaking community and the Brussels region):
the Flemish Region;
the Walloon Region; and
the Brussels-Capital Region.