This thesis explores attempts to intervene on behaviour in the urban night in Newcastle, in order to look at the relationship between the discourses and visions of policy-makers and the lived practice of cities. At its heart is an interest in how imagining and encouraging the emergence of new subjectivities has been a central part of the neoliberal ‘night-time economy’ – a term which I challenge as being too restrictive to describe the urban night. I seek to expand upon previous researchers who have too narrowly focused on the alcohol and leisure industry, abstracted from the rest of the night, which results in an inadequate description of the variety of actants involved in producing the subjectivities associated with the urban night. This thesis thus focuses on the four-way relationship between the built environment, legislation/policy, bodies, and subjectivities, as governed in the urban night. To do this, I conducted ethnographic and interview research with street-cleaners, taxi drivers, policy makers and bar staff in order to focus on the role of peripheral actors in producing the urban night. As thesis develops, I explore a ‘vocabulary of practice’ in order to set out the process of the emergence of subjectivities, and the different ways in which these are acted upon: in doing so, I introduce concepts of framing, assemblage, multiplicity, enunciation and affect, amongst others. This, then, draws from a diverse group of theorists, including the work of Felix Guattari, Giles Deleuze, Henri Lefebvre, Gregory Bateson, actor-network theory and non-representational theories. The thesis concludes by suggesting that further work is required on the relationship between policy formation and cities as practiced in everyday life, and that the theoretical approach used in this thesis provides suggestions as to how this might be developed.