and other researchers (see, e.g., Thompson, 1975) stressed that where common property existed, users had developed rich webs of use rights that identified who had a long-term interest in the resource and thus an incentive to try to avoid overuse. Few asserted that all common property regimes were optimally efficient or fair. Rather, the specifics of a particular regime had to be examined before presuming that an external authority should step in, violate local customs, and impose a new set of rules that were unlikely to be viewed locally as legitimate.
Another type of challenge came from game theorists. Early attempts to formalize commons situations using game theory typically posed the problem as a prisoners’ dilemma (PD) of the form described earlier, but extended the analysis from the classical two-player case to the N-person case (e.g., Dawes, 1980; however see Rubenstein et al., 1974; Stern, 1976, for early formulations that did not treat the commons as a PD game). When a PD game is played only once or is repeated with a definite ending time, a rational player has one—and only one— strategy that generates the highest immediate payoffs, assuming all players are using the same form of rationality. That strategy is to inform on the other players (called defection in the literature). Until recently, the dominant view has been that this one-shot, N-Person PD adequately models the nature of the situation faced in most commons settings. The research summarized by Kopelman et al. and Falk et al. in this volume shows that Hardin’s predictions hold under a one-shot condition with no communication, but not necessarily in a world where the game is played repeatedly, where there is no predefined endpoint, or where communication is possible (see Axelrod, 1984).
Some researchers have argued that games other than PD, such as the “assurance game” or the “game of chicken,” are more appropriate models for at least some of the situations facing users (Taylor, 1987). Unlike the PD game, which has a single equilibrium (and thus, each actor has a dominant strategy yielding a better individual outcome no matter what the other actor does), these games have multiple equilibria (and thus, neither actor has a dominant strategy), so both benefit from coordination.7
In a series of papers, Runge (1981, 1984a, 1984b) stressed that most users of a common-pool resource—at least in developing countries—live in the same villages where their families had lived for generations and intend to live in the same villages for generations to come. Given the level of poverty facing many villagers, their dependence on natural resources, and the randomness they all face in the availability of natural resources, Runge argued that it is implausible to assume that individuals have a dominant strategy of free riding. He suggested that users of common-pool resources in developing countries faced a repeated coordination game rather than a one-shot PD game. In such situations, all users would prefer to find ways of limiting their own use so long as others also committed themselves to stinting. Village institutions would provide mechanisms to enable users to arrive at agreements (within the village context) that would assure each user that others were conforming to the agreed-on set of rules. Thus, Runge and other