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There is a growing trend within both scientific and management communities to improve our ability to forecast and respond to abrupt shifts in marine ecosystems. This trend is evident in the increasing amount of work dedicated to understanding the mechanisms of ecosystem shifts and identifying ecological thresholds. Here I present findings from our efforts to characterize stressor-response relationships in marine ecosystems and to develop an ecological framework to define ecosystem-based thresholds for both human and environmental pressures. In addition, I will present results from our efforts to develop 1) state indices to reduce the time required to detect abrupt community-level changes in Northeast Pacific ecosystems and 2) early warning indices to track changes in the relative likelihood of a sudden ecological shift. The ultimate goal of this work is to develop reference points based on how the indices have performed in the past to enable scientists and managers to distinguish normal variability from changes signaling a major shift.