There is a global consensus and an ever-growing body of evidence that expanding access to clean household energy for cooking, heating and lighting is key to achieving a range of global priorities, such as improving health, gender equality, equitable economic development and environmental protection. In September 2015, Member States of the United Nations (UN) adopted the Sustainable Development Goals (SDGs), including Goal 7, which seeks to “ensure access to affordable, reliable, sustainable and modern energy for all” by 2030 and would be measured as the percentage of the population relying primarily on clean fuels and technology. This and other important developments, such as the UN Secretary-General’s Sustainable Energy for All (SE4All) campaign show that prospects have never been brighter for cleaning up air in and around the home, throughout the world. However, success is not guaranteed. The new analyses stemming from the WHO Household energy database demonstrate that progress towards the goal of universal access remains far too slow: more than three billion people still rely on polluting, inefficient energy systems to meet their daily cooking needs. And too many depend on polluting fuels and devices for heating and lighting.