Waste-to-energy (WtE) is one of the leading technologies for municipal solid waste (MSW) treatment in Europe. Recent trends indicate that WtE allows, apart from utilization of the energy content of waste, also the recovery of various valuable components. Hence, WtE can be included in the key technologies that can put the circular economy concept into practice. Secondary raw materials in the case of WtE are solid residues, especially IBA, as it is a secondary source, particularly of ferrous (Fe) and non-ferrous (NFe) metals and glass. A significant development in technologies for metals or glass recovery during the last decade can be noted. These technologies have become common part of WtE plants all over the Europe. The paper summarizes basic, concepts and principles of metals recovery from incineration bottom ash.