?Harald Dyckhoff led the chair of business theory, sustainable production and industrial control at the RWTH Aachen University, Germany, from 1988 to 2016. His current research areas are production and decision theory, sustainable value creation and performance measurement. He has published several books and papers on different topics of cutting and packing, production theory, data envelopment analysis and fuzzy set theory. Rainer Souren has lead the group of sustainable production and logistics management at Ilmenau University of Technology, Germany, since 2006. His current research areas are production theory, sustainable closed loop management as well as waste management and controlling. He has published books and papers on different topics of production theory, closed loop management, waste management and sharing economy.