Social marketing is the latest public health strategy deployed against a wide range of health imperatives, especially ones associated with people’s behaviour. This investigation examines the ‘social’ in such social marketing, by focusing on the relationships between the people, communities, organizations, institutions and material of one such initiative. Most studies determine the ‘effectiveness’ of a social marketing programme according to measurable outcomes. However, this has created a gap in knowledge about what actually happens as a programme is initiated at a local level, how constantly-changing social contexts influence its delivery, and how social marketing impacts people, especially marginalised populations. Rather than viewing social marketing as a form of ‘intervention’, which is typical of the ‘conventional’ approach, this investigation examines social marketing as an iterative and social process. Launched in 2008, Change4Life (C4L) is the English Department of Health’s first anti-obesity social marketing programme. C4L multimedia advertising is found throughout the English landscape, converting the built and virtual environment into a moral space. However, a key characteristic is the way such a national remit is converted into a wide range of specific initiatives at local levels. This investigation considers four case studies within one region of the UK to explore the varied ways in which a general social marketing venture is translated and implemented. By building up ethnographic accounts using participant observation, in-depth interviews, and interpretative analysis, these case studies illustrate how local health officials responded to the local tensions created by the national all-encompassing C4L programme, particularly in their attempts to relate C4L to ‘hard-to-reach’ communities. The diversity of their efforts highlights the limited applicability of the ‘conventional’ approach to social marketing. This investigation therefore suggests an approach for developing a more ‘social’ form of social marketing and contributes to the greater discussion on how to develop public health strategies that actively solve the underlying social problems of public health.