Whether it stems from babies born within the confines of a city or families migrating into municipal boundaries in search of a better life, the world’s urban population is growing by 65m people per year. This may at first seem daunting, but population agglomeration can be a good thing. Concentration of services and resource allocation leads to a smaller carbon footprint, and creates conditions for growth. In fact, it might even be fair to say that urbanisation is a key driver for development, as per capita economic activity increases at least 10 per cent with every 5 percentage point increase in urban population. Further, for every percentage point increase in the urbanisation rate, in many places there is more than a 2 per cent increase in gross domestic product per capita.

Three important qualifications apply: not all growth is equal; not all commercial gains remain in the place they were created; and not all economic activity is accounted for in formal statistical reporting. These implied nuances should not be interpreted as negatives, but instead reflect the incredible resourcefulness and creativity emanating from cities to attract investment, create jobs, and even improve the quality and standard of living for residents.

Cities are laboratories for invention. The time feels right to redefine traditional teaching about market failures to include informal markets, the globalisation of economies, and the notion of risk. What sounds like a great technological solution to someone sitting in a conference room in Silicon Valley might not appeal to the target beneficiary residing in a slum in Harare. Yet, these are the systems and processes we continue to embrace.