What concept did Elinor Ostrom study in the 2009 Nobel Prize in Economics research?

Elinor Ostrom studied common-pool resources in her 2009 Nobel Prize in Economics research.

Common-pool resources are resources that are difficult to exclude people from using but can be depleted through use. Examples include fisheries, forests, grazing land, and irrigation systems. Ostrom examined how communities can manage these resources without relying solely on government regulation or private ownership.

Her fieldwork and comparative research challenged the assumption that shared resources inevitably collapse through overuse. She identified recurring principles in successful local institutions, including clear boundaries, monitoring, graduated sanctions, and accessible conflict-resolution systems.

Ostrom shared the prize with Oliver E. Williamson. She was the first woman to receive the economics prize, while Williamson was honored for analyzing economic governance and firm boundaries.