The traditional polders in The Netherlands have been formed from the 12th century onwards, when people started creating arable land by draining delta swamps into nearby rivers. In the process, the drained peat started oxidizing, thus soil levels lowered, up to river water levels and lower. Throughout the centuries farmers have been adapting their agricultural system to lowering soil levels and occasional floods and invented new ways to organise themselves and keep sea and river water out – resulting in the building of hundreds of drainage windmills and later pumping stations to pump water from polders into the rivers and the sea. This development resulted in the creation of present-day polder landscapes that are characterised by grasslands on peaty soil with drainage channels, economically sustained by dairy farming, which harbour a rich flora and fauna. These systems function in a context of (among others) rising sea and river levels, continued lowering land levels, increasingly multifunctional use of land (urbanisation, recreation and tourism, nature conservation, culture conservation), interference of agricultural policies, and other interests. A plethora of government, non-government and private parties with intense negotiation practice make up the polder governance arena. The oldest of such organisations are the “water boards” with the mandate to provide safety from water threats for all citizens. The physical and institutional polder culture is indeed a crucial aspect of the Dutch national identity.