Small Island Developing States (SIDS) share a common vulnerability to climate change. Adaptation to climate change and variability is urgently needed yet, while some is already occurring in SIDS, research on the nature and efficacy of adaptation across SIDS is fragmentary. In this article, we systematically review academic literature to identify where adaptation in SIDS is documented; what type of adaptation strategies are taken, and in response to which climate change impacts; and the extent to which this adaptation has been judged as successful. Our analysis indicates that much adaptation research is concentrated on the Pacific, on independent island states, and on core areas within SIDS. Research documents a wide array of adaptation strategies across SIDS, notably structural or physical and behavioral changes. Yet, evaluation of concrete adaptation interventions is lacking; it thus remains unclear to what extent documented adaptation effectively and sustainably reduces SIDS’ vulnerability and increases their resilience.