A method for the catalytic decomposition of N2O in an N2O- and NOx-containing gas in the presence of a catalyst, wherein the catalyst contains a zeolite that has been loaded with a first metal chosen from a group of noble metals consisting of ruthenium, rhodium, palladium, silver, rhenium, osmium, iridium, platinum and gold, and with a second metal chosen from a group of transition metals consisting of chromium, manganese, iron, cobalt, nickel and copper, and in that the loading of the zeolite with these metals is effected by loading the zeolite with the noble metal and the transition metal simultaneously, also relating to a catalyst for this method and to a method for the preparation of the catalyst.