This article deals with the knowledge and skills related to tracks in the sand among nomadic and semi-nomadic populations with a predominantly pastoral focus in the Sahara and Sahel. Identifying a sought-after individual, interpreting the associated clues, catching up with it by following the trail – all this is an essentially pastoral know-how. The punctual examination of the footprint aims at identifying the individual who produced it, and the search for clues associated with the footprint enables the tracker to discern other elements interpreting more generally the behaviour of this individual in movement. Through the understanding of the spatial and temporal context, linear tracking of footprints, by implementing a hodological strategy, makes it possible to catch up with the individual in question. Furthermore, this chapter discusses the power structures between the men who are in charge of tracking as well as the confirmation, assurance or subversion of the social order it implies. Finally, the permanence and transformation of this common and essential know-how in the process of becoming sedentary are analysed.