Since its original publication, this book has proven increasingly influential to those working in political philosophy, human rights, global justice, and the ethics of international relations and foreign policy, particularly in debates regarding foreign policy's role in alleviating global poverty. The book asks: Which human rights ought to be the first honored and the last sacrificed? It argues that subsistence rights, along with security rights and liberty rights, serve as the ground of all other human rights. This classic work, now available in a thoroughly updated fortieth-anniversary edition, includes a substantial new chapter examining how the accelerating transformation of our climate progressively undermines the bases of subsistence like sufficient water, affordable food, and housing safe from forest-fires and sea-level rise. Climate change threatens basic rights.