What is justice? Questions of justice are questions about what people are due, but what that means in practice depends on context. Depending on context, the formal question of what people are due is answered by principles of desert, reciprocity, equality, or need. Justice, thus, is a constellation of elements that exhibit a degree of integration and unity, but the integrity of justice is limited, in a way that is akin to the integrity of a neighborhood rather than that of a building. A theory of justice is a map of that neighborhood.