The study guide describes the different approaches to the concept of “economic integration”. It allows determining the specific characteristics, goals, objectives and functions of trade organizations within each approach. The analysis of the stages and conditions necessary for the transformation process of various forms of trade organizations at each historical stage is conducted. It contains an analysis of the development and evolution of approaches to the study of the influence of concentration processes on the level of profitability of enterprises. The main indicators and parameters characterizing the process of concentration are summarized. The study guide proposes means for assessing the concentration processes in the retail market based on Russian Federal State Statistics Service data. The main methods and indicators for evaluating the effectiveness of mergers and acquisitions used in Russian and foreign practice are analysed.