The idea is controversial. Michael Mann, director of the Penn State Earth System Science Center in University Park, Pennsylvania, is sympathetic to the Green New Deal, but is not quite ready to downplay the contribution of the market. By contrast, Kevin Anderson at the Tyndall Centre for Climate Change Research at the University of Manchester, UK, thinks that time has run out for what he calls “incremental decarbonizing of the free-market economy”. Farhana Yamin, an environmental lawyer, has gone a step further. After three decades as an academic, adviser to governments and the UN, and a member of the IPCC, she has joined Extinction Rebellion, a movement that organizes non-violent civil disobedience, and explains why direct action is now the only solution.