The achievement of any meaningful development goals needs to change how develop and manage our cities. Rapid urbanization in developing countries demands a massive provision of infrastructure, public transportation, housing and jobs for their population, as well as a healthy environment. Consequently, urban areas in those countries contribute increasingly to climate change, and suffers its impacts. The climate co-benefits approach in this report refers to the development and implementation of policies and strategies that simultaneously contribute to addressing climate change and solving local environmental problems, which also have other development impacts. The co-benefits approach is especially important for developing countries, which have to overcome many challenges simultaneously with limited capacities and resources. Thus, the objective of this report is to examine the main obstacles, opportunities and challenges to implementation of climate co-benefit related policies in urban areas. The report focuses primarily upon sub-national processes, particularly in cities in developing countries, but the research also looked into the links of sub-national processes to national and international processes. The report relies on the results of research done in Brazil, China, India, Indonesia and Japan. It offers a series of lessons for understanding projects and policies that generate co-benefits and the factors that influence them. This report provides insight on successful ways to promote, design and implement the urban co-benefits approach in urban areas.