SUMMARY: This overview explores sustainable development in island contexts. More subtle and complex concepts of sustainable development have become manifest in the Sustainable Development Goals, with tensions between social, economic and environmental objectives at different scales as livelihoods acquire greater flexibility and islands face multiple challenges to development. Islands are part of rapidly changing and wider worlds, while sustainability is complicated by global change, as debates over strategies and time periods are accentuated in constrained island contexts. Development and sustainability have repeatedly acquired new meanings, hence requiring new analytical techniques, planning objectives and effective governance and management. Progress towards sustainable development in islands and island states is hampered by multi-scalar challenges, including limited biodiversity, migration, external interventions and directives, scarce human resources, weak management, inadequate data (and problems of interpretation), social divisions and tensions and simultaneous quests for modernity and conservation. The tourism sector emphasizes how sustainable development is particularly difficult to achieve in small islands where access to adequate livelihoods is important and limited change is possible.