Arctic ecosystems are characterized by persistent low temperatures, permanently frozen ground, and short growing seasons, properties which exert significant constraints on ecological dynamics. Arctic regions are also experiencing more rapid warming compared with lower latitudes, and as such, these ecosystems are among the most sensitive and susceptible to changes in climate and disturbance. Scientists have been documenting changes in ecological dynamics, including shifts in species distributions and community structures, altered phenology of organisms, physiological changes or adaptations, and ecosystem-scale processes all across the Arctic. These changes vary among habitats, organisms, geography, spatial and temporal scales. In addition, many species in the Arctic are important for subsistence activities such as hunting and fishing, thus documenting and anticipating changes to these ecosystems has great relevance to northern societies. These topics form the basis of this symposium, which will highlight recent advances in our understanding of arctic systems as well as the ecology of rapid environmental change. Speakers in this session will represent a diversity of questions, study organisms, habitats, and geographical focus, which will facilitate a synthesis of knowledge and improved and coordinated efforts for anticipating arctic change.