Statistics of mergers and acquisitions is a traditional direction of international statistics and a new direction of Russian ststistical science. In the published study, based on the recommendations of Eurostat and the organisation for economic co-operation and development (OECD) on improving business statistics in terms of methodological approaches to measuring the integration activity of economic entities, the main directions of processing and analyzing information on integration transactions that contribute to the development of statistical accounting of mergers and acquisitions in Russia are analyzed. The authors carried out a statistical analysis of integration processes and the main trends in the development of the Russian market of mergers and acquisitions in terms of economic sanctions and import substitution, and offered an econometric approach to assessing the integration activity of Russian companies. The article describes the main directions of statistical accounting and analysis of various aspects of the integration activity of economic entities. Proposals have been formulated to improve the collection and processing of data on integration transactions, as well as new approaches related to the collection and processing of data on mergers and acquisitions, in order to more fully and timely reflect the economic situation in the field of integration at the national and international level in the context of global transformation processes. The instruments for the classification of sector (industry) of the Russian economy on the degree of integration activity, which is based on the model of decomposition of mixtures of probability distributions, allowing to quantify the sectoral imbalances and to identify the class of the integration of the active sectors of the domestic economy before and after the introduction of economic sanctions against the Russian Federation were imposed.