Chapter 7 discusses the issue of governing the commons with social incentives. Common-pool resource exploitation is known as the tragedy of the commons. This metaphor is based on the assumption that human behavior is driven only by self-interest. Selfish users are unwilling to pay the costs of resource conservation because the benefits of doing so are shared collectively. This chapter offers an explanation for the conservation of a common-pool resource, namely individuals who consider the resource conservation to be their major concern are driven by social incentives. Besides material payoff, the pro-environmental identity obtains psychological payoff related to the resource conservation. Further, this chapter considers the interplay between the pro-environmental identity and the morally constrained one. The individual with internal moral constraints follows a moral rule imposing an extra cost on the resource extraction. A society can be sustainable to the degree that its members embody moral preferences and regulate themselves by moral rules.