The design of flue gas treatment equipment in municipal waste incineration plants worldwide varies according to the requirements with respect to pollutant emissions and resource recovery. Various combinations of individual separation processes may be encountered, such as dry particle separation, gas absorption (wet or dry), adsorption, catalytic or thermal conversion. The present comparison of different basic process alternatives indicates that firstly any degree of pollutant removal can be achieved by the available process technologies with corresponding expenditure of money and energy demand, secondly, German plants generally are more complex than plants in other countries due to more stringent separation and resource recovery efficiency requirements, and thirdly, a trend can presently be seen towards more simple and cheaper processes with simultaneous separation of several pollutants in one process step.