The previous chapters have analysed ten company cases within five sectors: electric power production, oil, pulp and paper, cement, and steel. This chapter compares these cases to shed light on whether, how and why companies have responded to the world’s first international emissions trading system. We commence with the three ‘models’ to guide the analysis, as set out in Chapter 2: companies as reluctant adapters, as innovators, or as socially responsible. Corporate responses in line with these models may affect pre-existing climate strategies or shape entirely new strategies. The EU ETS co-exists with other EU climate and energy policies; we expect to find that climate strategies are co-produced by company-internal factors as well as wider external contextual factors. Here we will analyse such factors within the framework of the three models, conditioning the effect expected from the ETS. This broader analytical perspective should help in explaining variation in climate strategies and identifying the conditions under which strategies emerge.