I model an economy featuring two representative firms in two countries, one in each country, where one firm innovates and generates technological unilateral spillovers. I analyze a partial equilibrium model in two different scenarios: in the first one, the innovating firm is under a domestic emissions taxation, while the other country does not implement any environmental policy. Government of the innovating firm introduces a tax credit aimed at incentivizing investment in cleaner abatement technologies. Finally, in the second scenario, the two countries take part to an international ETS. Comparisons among results from di¤erent scenarios are shown in the analytical part of the study. I conclude that, under specific assumpitons, overlapping regulations might be welfare improving.