In modern conditions, taking into account the scale of the tasks being solved, the complexity of developing digitalization systems and introducing them into the activities of enterprises is constantly increasing. The increase in development time and associated costs is affected by potential inconsistencies that arise due to discrepancies in the implemented processes of the system and the activities of the enterprise. Typically, such inconsistencies are identified at later stages of development. One of the components of this problem is the lack of formalized methods for checking the compliance of the enterprise’s activities, expressed by a set of models of user activity and activity, with the implemented system. Currently, compliance monitoring is carried out by an analyst based on his knowledge and a list of recorded requirements for the system. Such control is carried out at the level of the tasks being solved and does not allow us to correlate the methods of their implementation. It is proposed to eliminate this problem by developing a way of presenting activities that will eliminate the ambiguity inherent in the level of presentation in the form of tasks to be solved. The article presents an analysis of ways to represent activities, discusses existing approaches to modeling user activities (enterprise activities) and methods for representing system activities. The article describes a new model for representing activities through mechanisms that allows you to describe the activities of a group of users (employees) and the enterprise as a whole. The principles of objectification of mechanisms when drawing up an activity model and the rules for combining the mechanisms of individual actions into an activity model are proposed. The results obtained during the study will form the basis for developing a method for checking the correctness and compliance of the user’s (enterprise’s) activities and the activities implemented by the system.