Amid the bleaker assessments of other contributions, this chapter offers a rare success story, outlining how we have been quicker to mitigate the harm wrought on Earth’s atmosphere. This is, in part, due to the directly visible nature of our impacts: London’s ‘Great Smog’ in 1952; satellite images of a gaping hole in the Ozone layer in the 1980s; the accumulation of ground level ozone, reacting with lead in gasoline fumes, in Los Angeles; acid rain. These indicators led to a series of decisive measures: the UK Clean Air Act in 1956; the banning of CFCs beginning with the Montreal Protocol in 1987; the introduction of catalytic converters; and subsequent amendments to the US Clean Air Act in 1996. These successes aside, the chapter emphasizes the greater threat of air-borne particulate matter that continues to contribute to pollution and is harder to eradicate. This will continue to be an issue as forests are burned, as inefficient fuel usage for cooking in developing nations persists, and as industrial activities – twinned to the inexorable rise of urban populations – continue. The chapter ends on the hope that a combination of technological innovation, transformation of the global energy network and effective public policy can enact the fundamental changes needed to protect our atmosphere.