Advertising has a dual function for British public health. Control or prohibition of mass advertising detrimental to health is a central objective for public health in Britain. Use of mass advertising has also been a more general public health strategy, such as during the initial government responses to HIV/AIDS in the 1980s. We trace the initial significance of mass advertising in public health in Britain in the postwar decades up to the 1970s, identifying smoking as the key issue that helped to define this new approach. This approach drew from road safety and drink driving models, US advertising theory, relocation of health education within the central government, the arrival of mass consumption, and the rise of the "new public health" agenda.