Abstract. The article examines the essence of the concept of "digitalization" and approaches to the interpretation of the concepts of "system" and "processes" in the world of digitalization. It is noted that in theory there is no single unified model of the system and processes of digitalization, which complicates the management of the process of its implementation and assessment of effectiveness. The concept of digitalization is set out in dictionaries and legislative acts, regulatory and organizational and methodological support for the development of the country's digital economy and society. All of them, although different from each other, their essence boils down to the creation of a cyber-physical space. It is noted that, despite the great attention of researchers to these issues, research into the theoretical foundations of the digitalization process is at an early stage and certain theoretical and practical issues require a deeper understanding. There is no single unified model of the digitalization system and processes, which complicates the management of the implementation process. The main problems that need to be solved are the uncertainty of the conceptual apparatus, fragmentation of digitalization processes, insufficient integration, and difficulties in determining effectiveness. Approaches to defining the concepts of the digitalization system and processes are presented. The system is a strategic foundation that determines the rules of the game in the digital environment. Processes are tactical steps that an organization takes to achieve digital transformation. The digitalization system does not really exist separately from the processes - it is a dynamic system that is implemented through a sequence of tactical steps. The place of the concepts of "digitalization system" and "digitalization processes" in the theory of digitalization is determined.