Directly elected mayors are local government executive leaders who have been directly elected by the people who live in a local authority area. The first such political post was the Mayor of London, created as the executive of the Greater London Authority in 2000 as part of a reform of the local government of Greater London. Since the Local Government Act 2000, all of the several hundred principal local councils in England and Wales are required to review their executive arrangements. Most local authorities opt for the "leader and cabinet" model where the council leader is selected from the councillors, but in some areas the council proposes to adopt the "mayor and cabinet" model. Following a successful "yes" vote in a local referendum, a directly elected mayor is established to replace the council leader. Since 2007, councils can adopt the elected mayoral model without a referendum. Most authorities with elected mayors already had a ceremonial mayor and the two roles continue to exist concurrently. As of May 2015, 16 council areas are using the "mayor and cabinet" model of governance with a directly elected executive mayor.