We argue that an understanding of livestock farming as normative practice clarifies how sustainability is to be understood in livestock farming. The sustainability of livestock farming is first approached by investigating its identity. We argue that the economic aspect qualifies and the formative aspect founds the livestock farming practice. Observing the normativity related to these aspects will be the first task for the livestock farmer. In addition, we can distinguish conditioning norms applicable to the livestock farming practice which should be observed for competent performance of the practice. Failing to do justice to this normativity might affect the practice's sustainability only in the long term - this is especially the case with conditioning norms. Motives to observe normativity have, therefore, the character of an ultimate conviction regarding the flourishing of the practice. Finally, the sustainability of the livestock farming practice crucially depends on the broader food system of which it is part.