The lights are being switched off around the world at 8:30 p.m. on Saturday evening, to mark the 10th annual Earth Hour, and to draw attention to climate change. The initiative began in Australia in 2007 as a grass roots gesture by the World Wildlife Fund (WWF) Australia against man-made carbon dioxide emissions linked to a warming planet. In 2017, it will involve the switching off of electric lights for an hour in 7,000 cities across 172 countries, at 8:30 p.m.

"More connectivity is better." "The transfer of technology and best practices" through learning networks of cities are "incredibly important, more important than every climate summit that's ever been held in the world [...] " We spoke to him about his theory of a new, more connected world, the importance of knowledge exchanges between cities and how the challenges of inequality and environmental degradation in a rapidly urbanising world.