The article is a review of the recently pub­lished book “Evolution of Chromatic Accordion Key­board Systems: Genesis, Ergonomics, Classification” by N. A. Kravtsov. Nikolay Kravtsov is an accordionist, musicologist, inventor of a new accordion keyboard system, which is already widely used in educational and performing practice. The author of the review takes a brief excursion into the history of accordion construction, starting from 1829, when Cyrill Dеmian created a new mechanism for the accordion keyboard. The article notes that Kravtsov’s multifunctional system combines the advantages of previously existing types of accordion keyboards—three-row and organ-piano, being equally convenient for both traditional music-making and for performing music of academic genres, in particular, the avant-garde of the second half of the 20th century. The increased interest in instrumental folk music, as well as the demand for the accordion and button accordion in modern composers’ work, ensure the relevance of the book by N. A. Kravtsov.