This chapter assesses the rights governing access to globally shared natural resources, such as fish stocks, deep seabed minerals, and clean air. The international system is based on the principle of national sovereignty, which says that each state has absolute, perpetual, and exclusive rights within its national territory. This construction does not, however, match ecological realities. There is a stark contrast between states' territorial divisions and the biosphere's ecological connectedness. The chapter explores this tension and its relationship to decision-making in natural resource management. How can sovereign states manage the earth's resources if they are fragmented in separate territories that overlap complex ecosystems? This question is often approached using the ‘tragedy of the commons’ metaphor. When the metaphor is applied to the global commons, two main policy options emerge. The first is a coordinated approach building on the notion of a ‘common heritage of humankind’. The second policy option is a decentralized approach based on states' sovereign rights.
