Harmonization and standardization can be traced to two interrelated levels: harmonization and standardization as a process at the level of accounting standards and accounting practices. If the harmonization of accounting standards is observed, then a formal (de jure) harmonization which is operationalized through stages of disclosure (so-called formal harmonization of disclosure) and through evaluation (so-called formal harmonization of measurements) exist. In relation to accounting standards it is necessary to harmonize accounting practices and create a demand for material (de facto) harmonization. Effects of harmonization and standardization can be measured by using generally accepted index (C, H, I) which was successfully presented by various examples and opinions of the many authors. Although, there are certain contributions and controversies of statistical indices use for the purpose of measuring processes and states, it is necessary to develop a unique generally accepted index after accounting harmonization process with the goal of achieving global convergence degree.