Informal settlements made up of corrugated iron shacks and other materials are a ubiquitous feature in the megacities of Africa, Asia and Latin America. In response to the enormous influx of migrants from the countryside, the informal city experienced a phenomenal growth. While rightly criticized for their lack of hygiene and for their low-level living conditions, these shelters nevertheless provide planning strategies and possibly even a roadmap to a resilient city in an emerging territory.

The unregistered economic activities associated with them proliferate in a similar way and basic urban services are increasingly provided informally. Examples of these economic phenomena are microloans, bottom-up insurance or professions such as the "Kuré-Yalew" (refuse collector), who acts as an "urban miner" and thus contributes a valuable service to the community by recycling materials.