Slums may be housing a gradually reduced portion of the urban population as local policies take effect and as incomes increase. However, for the hundreds of millions at the bottom of the urban system, garbage pickup and removal is almost non-existent; toilets, let alone public toilets, are rare; running water to one's premises is an impossibility; well-funded public education is unavailable; and the quality of health services, transport facilities, leisure and open spaces, and even good local food markets is low. Investing in infrastructure is therefore an absolute necessity for the new urban agenda. In this regard, Goal 13 of the Sustainable Development Agenda, which urges countries to take urgent action to combat climate change and its impacts, could not have come at more auspicious time. Urban areas concentrate economic activities, households, industries and infrastructures which are hotspots for energy consumption as well as key sources of greenhouse gases.