The article summarizes the theoretical and methodological tools for studying the shadow economy in foreign and domestic scholarship. A comparative analysis of the existing and used diagnostic approaches for scaling the shadow economy, including review articles devoted to this paper, is carried out. The characteristics of scientific publications on countering the shadow economy are presented. In the course of the study, an analysis of features and directions of research by Russian and foreign scientists of the phenomenon of “shadow economy” was carried out, a comparison of the data array of scientific publications by bibliometric methods (VOSviewer) conducted on the international databases Dimensions, which is one of the new and is characterized by its objectivity, and the Scopus database, which is the most qualitative and widespread for the analysis of bibliographic data. It was revealed that studies in the format of articles on the shadow economy are mostly published in the humanities, which is more consistent with the Scopus database. For domestic articles, the eLIBRARY.RU scientific electronic library was used, as one of the largest and most authoritative bibliographic databases in Russia. It was revealed that the citation rate of Russian scientific works is low, but at the same time there are high counts of downloads and views, which indicates interest in this topic, but also the low scientific significance of these publications. According to the authors, in domestic and foreign scientific publications, there are insufficient recommendations on counteracting the shadow economy and, taking into account the conclusions of the analysis of methods for measuring the scale of the shadow economy, insufficient attention is paid to the regionalization of factors in the development of shadow economic relations, which would make it possible to increase the practical efficiency of the scientific research. A review of methods for measuring the scale of the shadow economy allows us to conclude that it is difficult to understand what the shadow economy is.