  On common accounts, we have a state of justice when everyone has their due. The study of justice has been concerned with what we owe one another, what obligations we might have to treat each other fairly in a range of domains, including over distributive and recognitional matters. Contemporary political philosophers had focused their theorizing about justice almost exclusively within the state, but the last twenty years or so has seen a marked extension to the global sphere, with a huge expansion in the array of topics covered. While some, such as matters of just conduct in war, have long been of concern, others are more recent and arise especially in the context of contemporary phenomena like intensified globalization, economic integration and potentially catastrophic anthropogenic climate change.