Reactions of silver cyanate with binary nitrogen oxides, NO and NO2, and ternary nitrogen oxohalides, CINO2, CINO, and BrNO, were studied by means of gas phase IR spectroscopy. The experimental data for the neat reactions of AgOCN with NO2 and AgOCN with CINO2 are compatible with the formation of an intermediate, short-lived OCN-NO2 molecule, which undergoes cleavage-rearrangement to give N2O and CO2. In contrast, NO does not react with AgOCN. The reaction of XNO (X = Cl, Br) and AgOCN is much more complex, leading to a mixture of NO, NO2, N2O, CO2, NCNCO, and X(CO)NCO. A reaction mechanism that involves the formation of neutral nitrosyl isocyanate, OCN-NO, has been proposed as the initial step. The two neutral intermediates, OCN-NO2 and OCN-NO, were computed by ab initio methods at the correlated MP2 level of theory and are discussed in terms of intramolecular stabilization by donor-acceptor interaction (negative hyperconjugation).