Small-scale furnaces for combustion of solid biomass can emit toxic or harmful gases and particulate matter. In this paper a representative selection of technologies for exhaust gas purification available on the market and in the development stage, respectively, is presented. Until now, no technology exists, which is able to reduce emissions of gaseous as well as solid pollutants from small-scale combustion. The enquiry about the state of the art revealed that the combination of electrostatic precipitators with catalytic post-combustion is a promising method. Results of experimental studies on such a combination are presented.