The 2024 Lancet Countdown SIDS Report explores the health-climate nexus in Small Island Developing States (SIDS), revealing significant vulnerabilities to extreme heat, food insecurity, and labor productivity losses. Between 2015 and 2023, SIDS populations faced escalating health risks due to heatwaves, with older adults and infants among the most affected. Adaptation measures, such as urban greening, early warning systems, and sustainable agriculture, are urgently needed but remain underfunded. The report calls for international action to reduce emissions and support locally driven efforts to protect health and ensure climate resilience in SIDS.