Coastal communities in Pacific Island Countries are particularly vulnerable to climate change impacts including sea-level rise, coastal erosion, tidal inundation, and the intensification of storm surge activity. In response, adaptation projects across the region have attempted to reduce exposure and overall vulnerability to these coastal pressures. This paper explores what happens once these projects reach communities: are effective and sustainable outcomes achieved, or can the implementation of adaptation projects lead to unintended negative outcomes and result in maladaptation? This paper investigates this issue in relation to two seawall projects implemented in communities on Vanua Levu Island, Fiji. We found that the seawalls have not been successful in achieving their primary aim of safeguarding communities against coastal pressures and have instead resulted in unanticipated negative outcomes for land and livelihood security. Of primary concern is the way that seawalls trap water along their landward sides—acting more like a dam—because of the ineffective design and construction of the seawalls and associated infrastructure. This paper concludes with a call to think more long-term about site-specific adaptation measures that actively involve and are driven by local perspectives in the planning, implementation, and maintenance process.