So far, the district heating and industry energy systems have essentially been optimized individually. For district heating, the use of waste heat from production processes is an important component of sustainable heat supply, while for industrial companies the external provision of waste heat is only an option if there is no other internal use and the feed-in is economically justified. The aim of the annex is to show synergy effects and potentials that result from the sector coupling of industry and DH networks in order to accelerate their increased use and to initiate more waste heat use. The Energieinstitut an der JKU Linz is cooperating to collect international practical examples and to derive how these industrial symbioses can be initiated and which business models are behind them.