Industrial Ecology (IE) is the study of material and energy flows through industrial systems. The global industrial economy can be modeled as a network of industrial processes that extract resources from the earth and transform those resources into commodities which can be bought and sold to meet the needs of humanity. Within the field of industrial ecology, PM researches the efficient management of material and energy at both a strategic level and the factory design level. At the strategic level the main questions regard the distribution of production tasks among different locations, both in global and regional context, such that resources availability is optimized and energy utilization is minimized. On the factory level, it is researched how to design new factories such that energy utilization can be optimized. An example would be to integrate into one factory different production processes that belong to different companies.