The decomposition of nitrous oxide was studied over Fe-ferrierite, Me-ferrierites and Fe/Me-ferrierites (Me: Pt, Rh and Ru). Flow as well as batch experiments were carried out and showed a synergy between Fe and Me ions. Ions of noble metals in Fe-ferrierite increased the catalytic activity in the sequence Pt < Rh congruent to Ru. Addition of NO substantially decreased the decomposition of N2O over Rh/ferrierite and Ru/ferrierite, but not over bimetallic ferrierites. NO (x) species created during the decomposition of nitrous oxide alone as well as with addition of NO, and employment of nitrous oxide labeled with O-18 allowed us to assume a changing decomposition mechanism in the presence of Me ions in Fe-ferrierites.