The recent development in the technology of catalytic emission control of stationary sources has been re vie wed. Special interest has been given to the non-selective (NSCR) and the selective catalytic reduction (SCR) of nitrogen oxides using ammonia, urea or hydrocarbons as reducing agents. Furthermore, the abatement of CO and hydrocarbons from gas turbines has been considered. Emphasis was laid on the development of catalysts to meet future tighter emission regulations as well as on informations about catalytic reaction mechanisms and progress in reaction engineering.