This report presents new data on the health of urban residents from nearly 100 countries, updating the first joint WHO-UN Habitat global report on urban health titled Hidden cities: unmasking and overcoming health inequities in urban settings. The new Global Report deconstructs the complex challenges of health and health inequity in cities everywhere. It presents a special analysis on the impact of persistent urban health inequities on achievement of the Millennium Development Goals (MDGs), and sets a baseline for the new global health and development agenda in the Sustainable Development Goals (SDGs) and Universal Health Coverage. It also presents evidence that in cities, progress in health depends not only on the strength of health systems, but also on shaping healthier urban environments.