This article focuses on the way department managers deal with flows in supermarkets in France. Their task is to manage department employees under the supervision of the head of departments or the store manager. Their position has changed over the course of the past 20 years concurrently with the successive reorganizations of stores. Indeed, in the late 1990s and mainly after the sudden turning point of the 2010s, the department managers’ tasks have evolved in brands such as Auchan, Carrefour, Cora and Géant Casino. Their sales skills regarding product management have been taken away from them and new skills are required instead, including management and human resources. However, this shift raises a major issue as they can no longer reach their original goal i.e. growing the profit margin by increasing sales in their department. This forces them to deal with a flow, in that case product flow with the help of another flow, that of the department’s employees.