The concept of need plays an essential role in defining legitimate health inequalities. The debate on equity in healthcare policy has so far evolved independently of the philosophical discussions of need. This article draws on moral and political philosophy in order to develop a conception of need that goes beyond the current dichotomy between universal lists and individual preferences. We build on Wiggins’ and Hamiltons’ insights in an attempt to further develop an institutionalist health economics. Our contribution suggests that (against mainstream economics and the dominant trends imported from moral philosophy) needs must be determined by explicitly political processes of negotiation and conventions. We propose an institutionalist approach to needs that emphasises the role of social processes in creating and consolidating specific and situated healthcare needs.