When EU waste law initially was established, its main aim was to prevent damage to human health and the environment, especially resulting from the uncontrolled dumping of waste. However, efficient use and saving of resources (i.e., what is now called a circular economy), have become important aims of waste law at least since 2006 and have been further been stressed and developed ever since. Waste law, therefore, is an important instrument to foster the transition to a circular economy. However, the application of waste law can also hinder innovative circular solutions. In the future, a more integral view on chemicals law, product law and waste law is needed to prevent such setbacks. In the development of waste law, the CJEU has figured and still figures prominently. With its ‘semi-legislative activism’, the Court has filled gaps the EU legislator had left.