The question of responsibility for climate change lies at the heart of societal debate over actions to address it. We may all have contributed to the problem, but some far more so than others. The United Nations Framework Convention on Climate Change (UNFCCC) established the principle of "common but differentiated responsibilities" among nations, suggesting that industrialized nations that had produced the greatest share of historic emissions bore particular responsibility for preventing dangerous interference with the climate system.

But society can assign responsibilities in other ways as well. This talk focuses in particular on the distinctive responsibilities of the major investor-owned producers of fossil fuels, describing new science on the scale of their contribution to the problem; the actions companies took and could have taken in response to the scientific evidence of climate change; and the evidence that civil society actions to hold companies accountable may be need to hasten our transition to a safe climate future.