The constitution (mostly from 1848) describes the functions and responsibilities of institutions that have executive, legislative and judiciary power. Parliament consists of an upper chamber (eerste kamer or Senate) of 75 members elected by provincial councils every four years, and a lower chamber (tweede kamer or House of Representatives) containing 150 members elected, also every four years, by proportional representation.

There are ten political parties currently represented, and coalition cabinets – composed of two or three parties, are the norm. The last elections were in November 2006 and saw swings to the Socialist Party (SP), a drop in support for the conservative VVD (previous coalition partners) and a fragmented vote split among the smaller parties such as the Green Left (GL) and right wing Party for Freedom (PVV). The Party for Animals were the first animal rights organisation to win seats in a European parliament.

The voting age is 18. Government comprises over 1,600 organisations and bodies, including 13 ministries, 12 provincial authorities and, since 1 January 2006, 458 municipal authorities. It also includes autonomous administrative authorities, such as police regions and chambers of commerce, and public bodies for industry and the professions. Members of the cabinet cannot be members of parliament.