The fishers in the Dominican Republic are facing the potential collapse of their fishery. The dominant narrative for why this is happening is known as the tragedy of the commons, popularized by Garrett Hardin through an article of the same name (Hardin 1968), although Hardin attributed his inspiration to William Forster Lloyd, a British economist and historian. The tragedy of the commons is the single most common narrative used to motivate the implementation of environmental property rights. In this chapter we discuss how it has been used and how it relates to theories and models of cooperation. We will also explore the limits of the idea by considering what it leaves out: namely, inequalities of power and influence. We conclude by considering additional theories that need to be considered when describing the causes of environmental degradation that need to be accounted for by environmental institutions.

The famous scenario that Hardin got from Lloyd is the one that sticks with most with people who have read his work. It is an image of cows on a pasture, with each herdsman deciding how many cows to place on this pasture. This decision is based on two components. First, the individual benefit the herdsman receives from placing on additional cow on a pasture, and the collective cost to the group if overgrazing occurs – too many cows can overgraze a pasture and degrade it. This collective cost is commonly referred to as a negative externality. The meaning of the term is intuitive: it represents the fact that the costs imposed by an individual on a group are “external” to the individual's decision-making or are not accounted for. The problem, as Hardin sees it, is that if each herdsman follows their own individual interest, the collective interest will suffer. It is called a “tragedy” because everybody loses. This gap between the interest of individuals and the interests of the group is known as a collective action problem, and it is closely related to the free-rider problem, which represents the temptation that participants have to free-ride on the contributions of others towards providing group benefits.