Today humanity uses, on average, the equivalent of 1.6 earths to provide the resources we use and to absorb our waste. A pathway to sustainable resource use is the circular economy. This concept aims at optimising the value of the resources used and to minimise the amount of resources used. The author addresses the question of what kind of law we need to realize a circular economy. He argues that many legal frameworks and rules on the national and the European level will have to be reconsidered, amended and some completely newly framed to foster a truly circular economy.This is the inaugural lecture which Professor Chris Backes delivered on 12 April 2017 on the occasion of accepting the Chair of Environmental and Planning Law at Utrecht University School of Law, Utrecht Centre forWater, Oceans and Sustainability Law.