The past half-century has seen a fragmentation of urban theory, one that is also evidenced in city-spaces. Cities have been labeled post-modern, post-industrial, post-colonial, mega, global, sustainable, creative, neoliberal, gentrified, themed, among a multitude of theoretical framings. All of these framings are descriptive of key dynamics witnessed in some (but not all) cities, but none describe well all those dynamics in any city. This is a problem showcased by current debates in urban theory today, particularly the recent debate between Scott and Storper (2015) in their discussion of the nature of cities, contested by such researchers as Mould (2016) and Roy (2016b), which calls into question whether a shared theoretical understanding of the ‘city’ is even possible. Indeed, this kind of debate has only intensified as urbanization continues its hyper-acceleration on a planetary scale (Brenner, 2014). As of 2009, over half the world’s population lives in a city (UNDESA, 2014). This means that roughly twice as many people are (re)producing their lived spaces in cities than the entire global population in 1900. An estimated one in eight people live in a megacity, or in cities with a population greater than 10 million; nearly half live in cities with a population below 0.5 million (UNDESA, 2016). By 2050, it is anticipated that as many as two-thirds of all people will be living in cities – with modest gains in already urbanized North America, Latin America, the Caribbean, and Europe and exploding growth in Asia and Africa – ultimately resulting in as many city-people at mid-century as live on the Earth today (UNDESA, 2009). Not all cities are created equal. Cities are often ranked competitively, based on a variety of criteria: population size, areal size (land consumed), and economic value. There are currently 214 cities ranked as global cities, those deemed most important to facilitating the global economy (Friedmann, 1986; Beaverstock, Smith and Taylor, 1999; GaWC, 2016). These are further ranked as alpha (49), beta (81), and gamma (84) cities – further demarcating the disparities between the command-andcontrol centers of global capital (while erasing those cities that are not considered competitive enough to be ranked) (GaWC, 2016). The megacity, by contrast, ranks cities by absolute population size, with 47 cities meeting the megacity definition of a population of 10 million or greater, and roughly 600 more cities having a population of 1 million or greater (UNDESA, 2016). Interestingly, there is overlap between urban definitions, in that cities defined by one definition become more likely (or less likely) to also meet an alternative definition (shown by the 40 out of 47 megacities that are also ranked as global cities).
