At the present stage of development, the world economy continues to rethink the need to introduce the concept of sustainable development into the activities of corporations, aimed at using an interdisciplinary approach, taking into account a combination of environmental, social and managerial factors. The process of integration of ESG factors is often slow and not without difficulties. Among other things, this is due to the problems of calculating ESG rankings, which are often incomparable and, as a result, prevent obtaining objective indicators of the involvement of economic entities in the process of implementing the principles of sustainable development. The problem of ESG rankings divergence is complex. It is recognized by experts at the international level and needs scientific justification of the sources of its occurrence, including issues of theory and methodology of assessment, the formation of a regulatory and resource base, as well as possible ways to solve it. The presented research was based on foreign and domestic materials devoted to the theory and practice of ESG data processing. Within the framework of this article, the authors identified and systematized the reasons for the divergence of ESG rankings, proposed their own interpretation of the concept of harmonization of ESG rankings and a step-by-step approach to the process of harmonization of ESG rankings. The developed recommendations can contribute to achieving convergence in the calculation of ESG indicators and interest all participants in the ESG transformation process at the national level, including ranking agencies, domestic corporations, investors, etc. All this will ultimately contribute to the implementation of the concept of sustainable development in Russia.