Abstract: The subject of this research is the content of the concept of “special circumstances” in the activity of internal affairs bodies. The author carefully examines the various definitions of the term “special circumstances”, as well as proposes the original approaches towards its comprehension. Within the framework of meaningful approach for understanding special circumstances as an objective characteristics of the activity of internal affairs bodies, the article suggests the term “special circumstance of the activity” and its definition in the broad (non-normative) and narrow (normative) sense. In the context of procedural approach, characterized by understanding special circumstances as a special institutional regime of the activity of internal affairs bodies, the author proposes the term “regime of special conditions” and formulates its definition. The scientific novelty consists in clarification of the conceptual and categorical framework in the area of law enforcement activity. The research results carry theoretical-applied character and may be used by the authorized subjects in development of the regulatory acts, as well as further research on the topic.