Key points
- The tragedy of the commons is not inevitable: some communities have been disproving it for centuries.
- Ostrom identified eight concrete conditions that make the self-management of a resource work.
- Public space, water and green infrastructure are urban commons that can be governed this way.
Governing the Commons (1990), by Elinor Ostrom, dismantles the idea that shared resources can only be managed by privatising them or placing them under state control. The dominant theory, Garrett Hardin's tragedy of the commons (1968), held that a common-pool resource ends up overexploited because each user pursues their individual interest, and that the only way out is private property or strict regulation. Ostrom showed with real cases — irrigation systems in Spain and the Philippines, alpine pastures in Switzerland, fisheries in Turkey — that communities can govern their resources sustainably through institutions of self-governance, and for that work she received the Nobel Prize in Economics in 2009.
Rather than relying on the state or the market, Ostrom shows that, under certain conditions, communities develop their own rules and monitoring systems to manage water, forests or fisheries over generations. Those local institutions adapt the rules to specific needs and to the environment, and they often manage better than centralised approaches. From her cases she drew a set of design principles that successful commons share: clear boundaries for the resource and its users, participation of users in making the rules, monitoring mechanisms and graduated sanctions, local conflict resolution, and recognition by higher authorities of the community's right to organise.
From natural resources to the city
Those principles have been applied well beyond natural resources, and especially to urban commons. Cities manage shared goods — public space, green infrastructure, water — that face the same dilemma: privatising them or over-regulating them tends to produce management that is less efficient and less equitable. Following Ostrom, urban communities can develop collective mechanisms to care for those resources without falling into either extreme, with their own rules, mutual monitoring and sanctions they agree among themselves. A neighbourhood that runs its own garden or square is applying, often without knowing it, the principles she described.
Polycentric governance and urban commons
The study of urban commons has since explored how citizens can take part in managing what is shared: community gardens, squares run by neighbours, shared mobility networks. Many of those goods require collaboration among very different parties, and this is where the polycentric governance Ostrom defended proves useful: several decision-making centres that cooperate and adjust to one another, instead of a single authority. In urban contexts, where dynamics are complex and users' interests diverge, that flexibility is an advantage over the single plan.
Information technologies have widened those possibilities: they allow the state of an urban resource to be monitored in real time and make it easier for residents to take part in decisions, which strengthens the capacity of communities to manage their goods. Ostrom's underlying idea remains the same: people can organise themselves to create effective and sustainable rules. Carried into the city, it shows how shared spaces can be managed more equitably, in a world that presses ever harder on the commons.
Frequently asked questions
What are urban commons?
Shared city resources — public space, green infrastructure, water, community gardens, shared mobility networks — that communities can manage collectively without resorting to either privatisation or strict state regulation.
What principles did Ostrom propose for managing shared resources?
Clearly defined resource boundaries, participation of users in rule-making, monitoring mechanisms and sanctions, and conflict resolution at the local level.
