Indonesia is among the largest 25 carbon dioxide emitting countries when considering only fossil fuels, and among the top three or five when emissions due to deforestation and land use change are included. Emission per capita from fossil fuels are still low in comparison with other countries, but have been growing fast, and are likely to overtake those from deforestation and land use change in the future. This chapter argues the importance for Indonesia to start developing strategies to mitigate its emissions from fossil fuel combustion. It analyses the main drivers of the increase in emissions, identifies the options and challenges in reducing the future growth in emissions. Policy options are reviewed that would enable the Indonesian economy to keep on growing, but with a much lower carbon output.