This chapter focuses on the big challenges that Small Island Developing States (SIDS) face. It discusses sustainable development challenges such as sea-level rise and storms and cyclones threatening the reversal of development progress made as well as more in-depth and context-sensitive challenges regarding social dynamics and political sovereignty. A major consequence of climate change that has become steadily evident is the rising of sea levels. The ongoing coronavirus pandemic highlights the fact that SIDS are also particularly susceptible to the effects of global health crises. Processes such as increased flooding of low-lying islands and coastal regions, soil erosion, and disruption of water systems may wash away the ground under the feet of SIDS inhabitants over time. The preamble of the United Nations Charter reaffirms the dignity and fundamental human rights of the individual, but also equality of nations, large and small.