Generally, the presence of foreign firms is most significant in waste management. Foreign firms are also active in wastewater treatment, and, to a smaller degree, in air pollution control. In waste management, Dutch, Austrian, German, and Danish technologies were ranked highly. Firms from these countries are active in solid waste salvage, and in landfill construction. Austrian firm Hoval is the biggest foreign supplier of incinerators.
Dutch firms are also active in waste incineration.
The presence of Italian firms, once marketing their technologies aggressively, is now limited. Waste recycling technologies are mainly dominated by German firms. Water and wastewater systems are introduced by a large number of foreign firms, including German, Austrian, French, Dutch, American, and British. It is difficult to determine the leader in this field, as the situation in the sector changes rapidly. Energy and air pollution sectors are primarily dominated by German technologies, followed by Austrian and American products.