Unlike private law contracts whose implementation system is mainly the responsibility of both parties, the implementation of public procurement contracts is subject to several controls that have proliferated in Tunisia along the evolution of public policies. Following a systemic approach, three different and yet interdependent levels of control can be distinguished: the control exercised by the contracting parties; the control exercised by authorities, which are in a certain extent dependent of the administration; and the, critical one, the control exercised by courts. The study of the interactions between these actors in a context characterized by the adoption of a new liberal Constitution and a new Code of Public Procurements, would make it possible to shed light on the tensions that continue to affect the general equilibrium of the system. The research concluded that, despite the changing context, the control system remains essentially focused on protecting the public interest.The research also concluded that the uncertainty surrounding the validity of the old regime's control norms and the deficiencies of the legal remedies' system remains and does not allow the monitoring authorities to maintain the balance between the public interest and the interests of economic operators contracting with the administration.