Through an examination of an investigation of commercial sexual practices conducted by an NGO, I explore how a public health programme creates its object on the ground through painstaking fieldwork. This paper is about a particular emplaced, embodied, visual practice; NGO fieldworkers identify and follow through the city women whose bodily dispositions identify them as ‘prostitutes’, although the women themselves vehemently reject this label. A particular politics of recognition emerges around uneven visibilities of women in the city. The fieldworkers labour to make the banality of ‘prostitution’ and its practices visible to the ‘prostitutes’ themselves, while at the same time cultivating a visual expertise in the recognition and classification of a putatively culturally specific bodily repertoire. Paying close attention to the techniques fieldworkers use to read public bodies shows how ordinary practices of urban bodily cultivation, everyday Dakarois technologies of gender, become progressively weighted with risk as they tangle with the evolving categories of a public health programme. Risk emerges here via a series of unequal exchanges within the visual economy of the city. Fieldworkers may find themselves exposed to new forms of reputational risk while they labour to define the social, sexual and semantic complexities of genn (going out).