Medical coverage often stops at borders, for both travellers and long-term migrants. Such patchiness imposes a de facto limit on free movement. This article considers this phenomenon not as a mere policy choice or technical matter, but as a form of territorial discrimination that is incoherent and even unjust. This legacy of nationally bounded social citizenship rests on a mistaken version of solidarity. Moreover, with growing mobility and rising expectations of medical coverage around the world, the fragmenting of safety nets (...) by the political honeycomb of statehood will become a vexing problem in coming decades. A proper understanding of the health sphere not only can justify incremental reforms that lessen territorial discrimination, without impairing either solidarity or sustainability. It also foreshadows a radically different vision of how social provision might work in a future global space beyond the nation-state. (shrink)