Tourism contributes to about 5% of total global greenhouse gas emissions, and the most common greenhouse gas, carbon dioxide (CO2), is emitted through goods and services related to tourism. Major tourism-related CO2 contributors include energy used for transport (from origin to destination as well as for local travel at the destination), development and operation of tourism infrastructure (e.g. hotels, road construction, heating and cooling) and various leisure activities. Thus, tourism contributes to some extent to global warming and climate change. This report, Sustainable urban tourism through low-carbon initiatives: Experiences from Hue and Chiang Mai, constitutes the background paper prepared for a CDKN-ICLEI learning programme. It provides a deeper analysis of the different factors which determined the course and the final outcome of the project ‘Sustainable urban tourism through low-carbon initiatives: Experiences from Hue and Chiang Mai’, conducted during 2012–2013. The report’s main objective is to provide key lessons from the sustainable urban tourism project through the analysis of different enabling conditions and obstacles that determined the course and the final outcome of the initiative.