As the human population increases, so too does the rate at which we modify the environment and produce waste. Nutrient pollution from terrestrial sources continues to increase. Marine waters have absorbed ~30 % of CO(2) emissions, and many marine species are already being forced to cope with increasing ocean acidification. Global sea surface temperatures have warmed at ~0.13 degreesC per decade since the mid-1980s and are predicted to rise a further 1-4 degreesC by the end of the century. Despite increasing research into these individual stressors, there is still only a limited understanding of how multiple stressors, such as increasing CO(2), temperature, and nutrient pollution, may combine to accelerate degradation of ecosystems. Yet, if we are to manage our marine environment to increase ecosystem resistance and resilience into the future, we need to understand how these stressors combine to cause ecosystem phase-shifts. ; Bayden D. Russell and Sean D. Connell