This week on One Planet, some common problems - greed and punishment, shame and the sharing of natural resources.
We're talking about the global commons, one of the key ideas of environmentalism. It first came to public attention in 1968 in an article in Science magazine by ecologist Garrett Hardin entitled "The Tragedy of the Commons".
Hardin described the problem of shared resources through the example of common land in a village. If I put another of my cows on the common land, I get all the benefit, but everyone shares the negative effects of over-grazing and environmental degradation - and if everyone does it, we all end up with skinny cows.
But does it have to be that way?
We speak to celebrated political economist Elinor Ostrom, who won the Nobel prize in 2009 for her work showing that commons management doesn't have to end in tragedy - she believes that communities are smart enough to regulate their own resources.
To test her theory, we go to the New Forest in southern England, where farmer have been commoning since the Middle Ages. Head Agister Jonathan Gerrelli tells us how they manage their common resources.
And Jennifer Jacquet of the University of British Columbia explains how communities can make individuals act less selfishly - by shaming each other into better behaviour.
As ever, tune in, have a listen and then let us know what you think. Email the team at firstname.lastname@example.org, or join us on Facebook and Twitter, the links are below.