Global climate change is likely to become a major cause of future migration. Small Island States are particularly vulnerable since territorial destruction caused by sea level rise poses a threat to their entire existence. This raises important issues concerning state sovereignty and self-determination. Is it possible for a state to remain self-determining even if it lacks a stable population residing on a specific territory? It has been suggested that migrants from disappearing Small Island States could continue to exercise sovereign control over their abandoned territory. Such an arrangement would allow them to retain a measure of self-determination. The question posed in this paper is whether this ‘deterritorialized state proposal’ is conceptually plausible and normatively acceptable. It is argued that the proposal is conceptually plausible if we adopt a gradual understanding of ‘self-determination’, but that its normative acceptability is weak even if it is supplemented with compensatory measures.