The City of Toronto is part of the Greater Toronto Area (GTA) (population est. 5,755,210 July 1, 2005), as defined by provincial authorities for urban planning purposes and is one of the fastest growing urban areas in North America. Toronto is also at the centre of the Golden Horseshoe, a densely populated region in south-central Ontario which is home to roughly eight million people[citation needed], or one quarter of the population of Canada.

The six former municipalities of the former Metropolitan Toronto (dissolved) were amalgamated into one municipality, and the former regional government system dissolved, by the Ontario government in 1998. This resulted in the creation of the ('megacity') City of Toronto, in political structure, as it is today. The current mayor of Toronto is David Miller.