Psychological understandings and individualistic theories of human behaviour and behaviour change have dominated both academic research and interventions at the 'coalface' of public health. Meanwhile, efforts to understand persistent inequalities in health point to structural factors, but fail to show exactly how these translate into the daily lives (and hence health) of different sectors of the population. In this paper, we suggest that social theories of practice provide an alternative paradigm to both approaches, informing significantly new ways of conceptualising and responding to some of the most pressing contemporary challenges in public health. We introduce and discuss the relevance of such an approach with reference to tobacco smoking, focusing on the life course of smoking as a practice, rather than on the characteristics of individual smokers or on broad social determinants of health. This move forces us to consider the material and symbolic elements of which smoking is comprised, and to follow the ways in which these elements have changed over time. Some of these developments have to do with the relation between smoking and other practices such as drinking alcohol, relaxing and socialising. We suggest that intervening in the future of smoking depends, in part, on understanding the nature of these alliances, and how sets of practices co-evolve. We conclude by reflecting on the implications of taking social practices as the central focus of public health policy, commenting on the benefits of such a paradigmatic turn, and on the challenges that this presents for established methods, policies and programmes.