In integrated biorefineries, physical and mechanical, thermochemical, chemical as well as biotechnological processes are applied in order to simultaneously obtain various products belonging to the classes: Food, feed, materials, chemicals, and energy, from various biogenic feedstocks. The focus on the production of more than one product is also expected to increase flexibility to changing market prices. This chapter introduces to bioeconomy and biorefineries based on various substrates, such as biowaste, oil/fat and sugar/starch as well as green biomass, currently under operation in Germany. For each substrate, process and scale as well as products are illuminated. Furthermore, future challenges of currently operated processes are discussed.