This short paper offers one vision of the “person-centred justice” ideal. Welfarism is the idea that government should always try to make individuals’ lives go better, for them, than they otherwise would overall. Welfarism is a normative theory applicable to public policy generally, but one which has distinct consequences in the realm of law and legal systems. They are considered just to the extent that they generate the best possible expected welfare consequences for all of the individuals who are affected by them. Welfarism is radically person-centred because it requires lawmakers to treat each individual affected by their work as a distinct locus of value, including those who have otherwise been subordinated or ignored. This paper introduces the theory of welfarism, with particular reference to the reform of law and legal institutions.