In the context of the global economy, some developing countries are seeking to develop their productive systems to create a stable economic structure. In this context, the Tunisian government has launched in the 1990s a new industrial policy oriented towards the support of R&D and of technological innovation. This paper analyzes this policy, focusing on the national innovation system (NIS). First, it deals with the theoretical developments related to the systemic approach of innovation. Then, it outlines the institutional, organizational and financial measures implemented to support the establishment of a NIS. Finally, it attempts to show that the participation of political authorities to develop a NSI will be insufficient since the interactions between different actors in this system are limited. JEL codes: O32, O38