The urban world is dominated by a small number of centres that are the command and control points for global capitalism, the world’s dominant economic system. Such centres are distinguished not by their size or their status as capital cities of large countries, but by the range and extent of their economic power. They are the locations for the key individuals, institutions and organisations that manage, manipulate, dictate and determine the formation and reproduction of capitalism across the world. These attributes give such cities a disproportionate and exceptional importance, so that they occupy dominant positions in the global urban hierarchy. So pre-eminent is their status and so powerful and pervasive are their influences that many analysts argue that they merit designation as world cities.