This chapter examines the relationships between cities and their desire for economic growth through the lens of the knowledge economy as a context within which more localised innovations sit. City elites and urban growth coalitions share common aspirations reflected in the search for symbolic and material advantage, which includes being attractive to inward investment by global capital. Whilst urban scholars have examined the sustainable city, less emphasis is placed on the relationships between knowledge, the city and experimentation from a social epistemological point of view in the climate of neoliberal capitalism. It examines the idea of experimentation in terms of the forms taken by cities in contemporary capitalism and the attribution by politicians, officials and expert cultures to its potential. In the competitive politics of global-urban hierarchies, cities embrace experimentalism to demonstrate to other cities, selected entrepreneurs, innovators and universities that they mean business.