There is a “downward spiral” in today’s recycling, accumulating wastes and losses by lacking and/or inefficient recycling. In order to circumvent this, material and product systems must be understood on a fundamental level. In this part, Markus Reuter from the SMS Group demonstrates the results of various simulation examples for analyzing large circular economy systems, and perform simulation based design for recycling. The connection to detailed product composition and metallurgical flowsheets linked to recycling and recycling labels will be made. In addition, energy analysis will be used to show the efficiency of systems on a thermodynamic basis, linked to process simulation as well as LCA.