In modern international law, permanent sovereignty over natural resources has come to entail duties as well as rights. This study analyses the evolution of permanent sovereignty from a political claim to a principle of international law, and examines its significance for a number of controversial issues such as people’s rights, nationalization, and environmental conservation. Although political discussion has long focused on the rights arising from permanent sovereignty, Dr Schrijver argues that this has been at the expense of the consideration of the corollary obligations it also entails. His book thus identifies new directions sovereignty over natural resources has taken in an increasingly interdependent world and demonstrates its relevance to current debate on foreign-investment regulation, the environment, and sustainable development.