The authors use a comparative politics framework, examining electoral interests, policy-maker's own normative commitments, and domestic political institutions as factors influencing Annex 1 countries' decisions on Kyoto Protocol ratification and adoption of national policies to mitigate climate change. Economic costs and electoral interests matter a great deal, even when policy-makers are morally motivated to take action on climate change. Leaders' normative commitments may carry the day under centralized institutional conditions, but these commitments can be reversed when leaders change. Electoral systems, federalism, and executive-legislative institutional configurations all influence ratification decisions and subsequent policy adoption. Although institutional configurations may facilitate or hinder government action, high levels of voter concern can trump institutional obstacles. Governments' decisions to ratify, and the reduction targets they face upon ratification, do not necessarily determine their approach to carbon emissions abatement policies: for example, ratifying countries that accept demanding targets may fail to take significant action.