Unitary authorities of England are local authorities that are responsible for the provision of all local government services within a district. They are constituted under the Local Government Act 1992, which amended the Local Government Act 1972 to allow the existence of counties that do not have multiple districts. They typically allow large towns to have separate local authorities from the less urbanised parts of their counties and provide a single authority for small counties where division into districts would be impractical. Unitary authorities do not cover all of England. Most were established during the 1990s and a further tranche were created in 2009. Unitary authorities have the powers and functions that are elsewhere separately administered by councils of non-metropolitan counties and the non-metropolitan districts within them.