In the present review the story of ICNS concept evolution, current notions of its structure and function and data on nervous coordination of the heart, in which ICNS can play a major role, are discussed. For today the doctrine of intracardiac nervous system experiences the second birth. It is shown that the ICNS contains a huge number of neurons with diverse activity patterns, forming local networks and releasing diverse neurotransmitters, thus being an autonomic integrative center. The opinion that the discovery of the ICNS functions and the term «intracardiac nervous system» itself belongs to North-American authors becomes increasingly widespread in literature. Actually, the detailed study of the ICNS was carried out in 1960–1980 by the groups headed by G. I. Kositsky and M. G. Udelnov and belongs to uncontestable Russian priorities.