What is the vulnerability–fragility nexus in the SIDS context? In this chapter, we first make a diagnosis about the past and current state of SIDS’ fragility using a number of well-known and more original indicators. We find that the group is heterogeneous, and SIDS usually show good levels of governance and absence of large-scale conflict in the contemporaneous period. However, high level of criminality is observed in a number of SIDS, particularly in the Caribbean (mainly due to drug trafficking as noted above). Second, while fragility in SIDS appears disconnected from usual structural drivers of fragility such as income and human development, we propose that fragility of SIDS should be analyzed through their somewhat common but group-specific vulnerabilities that harm sustainable development such as structural economic vulnerability (smallness and remoteness, dependency on volatile inflows of foreign trade, remittances or aid) and vulnerability to climate change (sea-level rise and cyclone activity).