Non-metropolitan districts, or colloquially 'shire districts', are a type of local government district in England. As created, they are sub-divisions of non-metropolitan counties (colloquially shire counties) in a so-called "two-tier" arrangement. In the 1990s, several non-metropolitan counties were created that are unitary authorities and also have non-metropolitan district status. A third category is the districts of Berkshire, which are non-metropolitan districts that are unitary authorities, but without non-metropolitan county status.