Is justice an ideal, for ever beyond our grasp, or something that may actually guide our practical decisions and enhance our lives? At the heart of Sen's argument is his insistence on the role of public reason in establishing what can make societies less unjust. But there are always choices to be made between alternative assessments of what is reasonable, and competing positions can each be well defended. Rather than rejecting these pluralities, we should use them to construct a theory of justice that can accommodate divergent points of view. Sen also inspiringly shows how the principles of justice in the modern world must avoid parochialism and address vital questions of global injustice.