The topic of the circular economy for plastics has attracted a great deal of attention: New technical processes to recycle plastics are being developed. Numerous political activities are being initiated at international, European, and national level in order to set new priorities. The political processes are then taken up in the regulations that form the legal basis for the actions of the government, society, and the economy (and the recycling industry in particular). However, there are often uncertainties in the design and interpretation of the legal framework, which in turn can adversely affect the development and market opportunities of new, innovative processes. The European waste hierarchy has a significant influence on the legal framework and its design and interpretation. The existence of various interfaces between waste law and other areas of law shows that the development of a successful circular economy requires both new thinking and overarching regulatory concepts. They should be based both on waste-prevention and on fostering making use of recycled raw materials.