The monograph reveals the theoretical and methodological foundations of the engineering of the information security management system of modern process-oriented enterprises, taking into account the basic system-forming principles of the theory of organizational systems. The content of the monograph is the result of a critical analysis of numerous professional publications in terms of their compliance with the basic principles of the general theory of organizational systems. It includes the results of the author's scientific research and their practical approbation during the implementation of many consulting projects at real enterprises. Considerable attention is paid to the analysis and synthesis of the conceptual framework of process management. From the system positions, the prospective author's methodology of selection, composition and graphic description of technological and management business processes is laid out, taking into account the possibility of conducting an audit of information security risk management of a modern process-oriented digitalized enterprise. The monograph is aimed at researchers, managers and specialists in information security of enterprises.