Coastal wetlands provide many ecosystem services. In addition to providing critical habitat for fish and wildlife, coastal wetlands improve water quality, store carbon, protect coastal communities from storms, support fisheries, and provide recreational and educational opportunities. However, in the face of climate change and accelerated sea-level rise, there is concern that some of these ecosystem services may not be available for future generations. There is concern that coastal wetlands will be transformed as critical ecological thresholds are crossed. An ecological threshold is the point at which a comparatively small environmental change triggers an abrupt and disproportionately large ecological response. Due to their position at the land-water interface, coastal wetlands are highly vulnerable to small changes in inundation, salinity, land use, and climate. In this presentation, we provide examples of threshold responses from coastal wetland ecosystems. We also present a conceptual framework highlighting the linkages between abiotic stress, climate-driven ecological thresholds, and ecosystem transformations. We describe anticipated future ecological transformations for coastal wetlands and contrast them with transformations in the recent past (1850-present). By understanding ecological thresholds and transformations, we can better anticipate future change and develop strategies to promote adaptation and coastal resilience.