The circular economy is about fundamentally changing the way we think about recyclable materials, moving away from the linear “take-make-waste” throwaway culture and turning to the efficient use of resources in the context of the energy transition. Energy, resources and raw materials can be restored, renewed or repurposed through the use of optimised processes. The circular economy means preserving the economic value of materials and reducing the environmental impact and pollution involved in production processes. There is no waste of precious resources. Materials are designed in such a way as to make recycling a viable option, using chemical or mechanical processes, for example. The research scientists at the ZSW are exploring new technologies, production processes and materials for environmentally-friendly and sustainable cycles. Only a move away from straight product “lifelines” to cycles following the “cradle-to-cradle” (C2C) principle will be conducive to lasting structural sustainability in the energy transition.