Since becoming Mayor of London in 2016, he has declared a climate emergency, introduced the world’s first Ultra-Low Emission Zone, built hundreds of kilometres of new cycle lanes, led a drive for affordable insulation in council homes, and turned London into the first ever ‘National Park City’. But with every year bringing more wildfires, extreme temperatures and flooding – and with around 4000 people still dying prematurely from London’s polluted air every year, with older, working class and ethnic minority Londoners most affected – there is so much more to do. Now, Sadiq draws on his experiences to identify the seven ways environmental action gets blown off course. And he reveals how to get it back on track.