Over the past few decades, attempts at adaptation to climate change (current and future) in the Pacific Islands have largely failed to be either effective or sustained. Among the many reasons for this failure may be that most adaptation strategies have been designed and driven by outsiders rather than by persons familiar with island contexts and diversity, especially the sociocultural nuances of particular situations. In a series of eight thematic case studies, written by scientists with an intimate understanding of the Pacific Islands, this chapter explores the reasons behind adaptation failure and explains what needs to improve in the future for adaptation to be both effective and sustained. Case studies focus on rural seawalls, relocation and peripherality as a proxy for autonomous community coping, climate finance, island food systems, adaptation project design, livelihood sustainability and inter-island resettlement. The goal of this chapter is to inform stakeholders how to optimise outcomes from future adaptation interventions, something that is becoming daily more urgent as the pace of twenty-first century climate change increases.