We present to Russian-speaking audience a translation and commentary on the classification of inborn errors of immunity presented at the end of 2019 by the Committee on Congenital Immunity Errors at the International Union of Immunological Societies (IUIS). Inborn errors of immunity, or, as they were called earlier, primary immunodeficiencies, is a rapidly expanding class of diseases that includes the most diverse congenital pathologies which can manifest at any age by heterogenous symptomes. Clinical masks characterize these diseases, hence the time from the onset of clinical disorder to the final diagnosis may take many years. A doctor of any specialty encounters these patients, and the molecular mechanisms of pathology concern different organs and systems of the patients. The classification consists of ten tables covering more than 400 syndromes and their corresponding genes, or associated chromosomal abnormalities. This is a tool, which allows navigating a wide variety of different primary immunodeficiencies, autoimmune and autoinflammatory syndromes, complement defects, and bone marrow failure syndromes. We hope that, due to translation, current knowledge about these various diseases will become more close and available to the Russian-speaking audience.