International audience This research relates to a 4-year study of the implementation of a financial and accounting internal control (FAIC) system in a medium-sized French university. More particularly, we examine the interactions between a new FAIC system and certain university actors to analyze the social and organizational phenomena taking place in French universities. The paper adopts a critical approach. We draw on the theoretical framework of boundary objects developed by Star and Griesemer (1989), and conceptual extensions incorporating the concepts of intermediary objects (Trompette and Vinck, 2009; Vinck, 2009), to analyze a situation of failure. The research question is the following: How does an accounting system with all the theoretical features required to be a boundary object ultimately remain at the level of an intermediary object? Relying on a qualitative study, the case of the French university offers the possibility of identifying the causes of the difficulties in cooperation (coordination or cohesion) between the financial departments and the accounting department. Especially, a reflexive approach based on a longitudinal research design allows opening up the black box formed by the FAIC system, and examining its performativity in the sense of provoking, instituting, constituting, making something take place (Muniesa and Callon, 2007). Findings show that the FAIC system is only an intermediary object for which “equipment” work is problematic, thus conferring to the boundary its other nature, that of a limit. These findings add to our understanding of problems to be solved in the way new accounting practices are implemented in public organizations, and then of how to set up a performative New Public Management. Moreover, we highlight a theoretical insight of the boundary object concept, i.e. its possible change’s obstruct nature.