Livestock markets are pathological sites in which contrasting biopolitical regimes compete to reconfigure agricultural practices and identities. Whilst the circulation of cattle is central to agricultural geographies, little is known about the practices of cattle trading or the role of livestock markets in cattle purchasing. Drawing on recent attempts to conceptualise the process of marketisation, this paper seeks to invigorate research into livestock markets. Specifically, the paper conceptualises cattle purchasing as a market encounter in which socio-technical arrangements, devices and bodily performances entangle cattle and farmers, enabling markets to work. Using data collected from interviews, focus groups and participant observation at livestock markets in England, the paper makes two contributions. Firstly, the paper shows how farmers’ cattle purchasing practices are organised by practices of ‘fluid engineering’ that seek to maintain the ‘farm system’. Secondly, the paper shows how at livestock markets, these strategies are mediated by front and backstage ‘market displays’ by farmers and auctioneers which produce market price through a series of performances that are carefully spatially and temporally ordered. Specifically, these displays perform specific rural and agricultural identities, such as the ‘genuine’ or ‘good’ farmer. In creating these spatial frames, frontstage displays diminish the relevance of backstage displays that rely on abstract calculations by distant others. The paper therefore reveals the intense entanglements and socio-technical work that is required to make cattle markets function and their wider relevance for the management of livestock diseases.