Coconstitutionalism is where two institutional cultures exist in a complex semi-autonomous relationship to each other. The model of asymmetrical devolution that has emerged in democratic Spain has been called "coconstitutional" in that it is neither a federal nor a unitary model of government: autonomous nation-regions exist alongside and within the Spanish nation-state in a relatively dynamic relationship. Since 1997, the UK government has pursued a similar coconstitutional model of devolution with regard to its nation-regions.