The article deals with the concept of investigative work as an integral part of operational investigative activities, in the context of its capabilities and significance in the activities of operational units of internal affairs bodies. The opinions of prominent scientists on the concept of investigative work in the narrow and broad sense of the word are discussed and analyzed, which largely differ in content and volume. In the first case, we are talking about the search for a known identified person, a suspect (accused) of committing a crime, or a person who has gone missing. Search in the broadest sense is considered as a set of measures, the first of which is the identification of the person to be searched, as well as other objects of evidentiary value that are subject to detection. Investigative work, based on the complex use of operational-investigative and criminal-procedural measures, some authors tend to consider as an independent interdisciplinary concept, partially subordinated to two different areas-criminal proceedings and operational-investigative activities. Based on the results of the analysis of various approaches to investigative work, we propose a definition that clarifies various aspects of the work of operational (search) divisions of the internal affairs bodies in this area, carrying out the search and identification of various categories of citizens.