THE SYSTEMIC APPROACH TO NATIONAL INNOVATION SYSTEMS IN A KNOWLEDGE-BASED ECONOMY Ioan Moise Achim, “1 Decembrie 1918” University of Alba Iulia Teodora Popescu, “1 Decembrie 1918” University of Alba Iulia ABSTRACT: The aim of this paper is to present the concept of National Innovation Systems, their history and role in the understanding of a systemic approach to research, development and innovation at national and global level. We will present a brief introduction to the main operational concepts and the history of the concept, from its beginnings to the present times. Key words: National Innovation Systems, knowledge-based economy; JEL codes: O31, O32, O43.