The Tragedy of the Commons


The UK will host the 26th UN Climate Change Conference of the Parties (COP26) in Glasgow on 31 October – 12 November 2021. The COP26 summit will bring parties together to accelerate action towards the goals of the Paris Agreement and the UN Framework Convention on Climate Change. The UK is committed to working with all countries and joining forces with civil society, companies and people on the frontline of climate change to inspire climate action ahead of COP26.

This summit theme of working together is closely linked to the problems associated with the Tragedy of the Commons. The phrase ‘tragedy of the commons’ was first coined by the biologist Garrett Hardin in 1968. It describes how shared environmental resources are overused and eventually depleted. Hardin compared ‘shared resources’ to a ‘common grazing pasture’, whereby individuals with rights to the pasture graze as many animals as possible, acting in self-interest for the greatest short-term personal gain. In time, the pasture is over grazed by the individuals and the shared resource is exhausted. Here are some real-world examples of the tragedy of the commons.

Groundwater in Los Angeles

Landowners around Los Angeles each have rights to use the water pumped up from wells on their land. This water is part of a regional groundwater aquifer, so each landowner is ultimately pulling water from the same pool. As the city grew in the 1930s and 1940s, the amount of water drawn from the underground aquifer increased each year to meet the needs of the growing population. Eventually, residents drew so much water from the aquifer that the supply reached levels that left the aquifer vulnerable to saltwater intrusion from the nearby Pacific Ocean. Facing potential water shortages, and possible destruction of the renewable water resource they depended on, the water users created a voluntary organisation to discuss how to manage and conserve the groundwater for the future.

los angeles

Unregulated Logging

The tropical rainforests are a common resource that everyone in the world benefits from. In some parts of the world, vast expanses of dense rainforests aren’t governed or owned in a way that allows effective management for resource extraction. Timber producers are driven to remove as much timber as possible as cheaply as possible. The result is that logging irreparably damages thousand’s acres of rainforest each year. Although some laws protect some forests from destructive logging practices, illegal logging continues – particularly along boundaries between countries, where the laws may be different on each side of the border.


Ocean Garbage Gyres

The oceans are an excellent example of a shared resource. No single authority has the power to protect all the oceans. Instead, individual nations manage and protect their own coastal waters, whilst leaving the vast areas of shared common space vulnerable to use and abuse. Throughout the world’s oceans, garbage has begun to accumulate in the centre of circular currents, or gyres. This pollution, especially plasticsdegrade the ocean’s ecosystem and worryingly are entering the food chain.

ocean plastic


Garret Hardin proposed two ways to avoid the tragedy:

  1. Assign ownership of the resource (eg. an aquifer) to the State, or
  2. Divide the resource into parcels (eg. as volumetric extraction entitlements from the aquifer) and assign the parcels to individuals as private or individual property.
    Elinor Ostrom suggested a third option, namely:
  3. Allocating ownership of the resource to a defined group of ‘commoners’ as common property.
    All three approaches (government-based, market-based and community-based) should be considered carefully for each individual situation with the best solution often involving a ‘polycentric’ blend of all three approaches.


  • ‘Economics for Collaborative Environmental Management: Renegotiating the Commons’ by Graham Roy Marshall