Non-thermal N 2 /O 2 plasmas are known and have been observed to generate NO at bulk temperatures much below those necessary for thermal N 2 oxidation. NO yields can even exceed those expected based on the bulk thermodynamic equilibrium. These NTPs contain radicals, ions, and vibrationally excited molecules, and kinetic models that incorporate the reactions of these excited species have been applied to microwave, pulsed-power glidingarc, glow discharge and stationary plasmas. These models recover observed NO yields and even the densities of intermediates. These models suggest that the same Zeldovich mechanism is at play in NTPs as in thermal oxidation. NO yields have been reported to increase over a non-zero background when a radio frequency, microwave or dielectric barrier discharge plasma is combined with a catalyst. Patil et al showed that the extent of that increase is catalyst-dependent, in experiments comparing a variety of metal oxides within a packed-bed, dielectric barrier discharge reactor. Similarly, introduction of WO 3 and MoO 3 down-stream of either an inductively coupled high frequency plasma or microwave plasma was observed to increase NO yields over background. In all cases, the observed improvements are with respect to significant background NO yields. Models to qualitatively or quantitatively explain these observations have not been reported.