Although climate policies target primarily CO 2 , they may indirectly have an impact on air pollutants and thus on air quality. Here we look specifically at the co-benefits of various European post-2012 climate policy scenarios related to air quality in the Nordic region. We analyse how caps on emissions, expansion of the European Union (EU) Emissions Trading System, carbon taxes, and Russian and non-EU Eastern Europe participation after 2012 will influence emissions, air quality, avoided abatement costs, welfare effects, the regional environment and human exposure to particulate matter in the Nordic countries. We find that stricter targets will contribute to reduced emissions of air pollutants, and benefits to ecosystems and human health, which would have required substantial abatement costs if achieved by application of 'end-of-pipe' measures. Due to the assumed use of the flexibility mechanisms, reductions in emissions in the Nordic countries are smaller than in other regions, but the Nordic countries benefit from reductions in emissions in nearby regions. The more sectors that are included in the emissions trading scheme, the greater the emission of air pollutants. If Eastern Europe and Russia were to abandon participation in a climate agreement, the EU and Norway would have to undertake more emission cuts at home in order to meet the same targets. This would benefit ecosystems in southern Scandinavia, but acidification would increase in the north because of increased emissions in Russia.