This author's conference is for Mathias Risse's forthcoming book The Grounds of Justice: An Essay on Global Political Philosophy. In this book, Risse, who is Associate Professor of Public Policy and Philosophy John F. Kennedy School of Government, focuses on the philosophical question of whether there are principles of justice that apply not only within but also across states. He argues that the “grounds” of justice are the norm-generating considerations or conditions that must be present for demands of justice to be applicable. These grounds, that is, are the considerations based on which the distribution of some goods must be justifiable to a set of individuals. Until not long ago much political thought assumed that the applicability of principles of justice was limited to the state (so that those grounds would consist in some features of shared membership in a state), and even where this was not assumed little effort was made to assess what justice demanded among those who did not share a state. A competing view that has recently gained prominence insists instead that the grounds of justice consist in common humanity whereas shared citizenship plays no essential role in assessing how demands of justice apply. This book develops a pluralist approach to the grounds of justice. There are different grounds on which individuals may make demands on each other that bear on the distribution of certain goods and that we should understand as demands of justice, and those generate different distributive principles that should all be considered principles of justice. This view (as Risse will develop it) still accords special normative importance to the state (or supports what he calls the “normative peculiarity of the state”), but also sees what the state can do as constrained by grounds of justice other than shared membership in a state.