The article deals with some aspects of Tugan-Baranowsky’s contribution. Section 1 presents a brief explanation of Tugan’s disproportionality crisis theory. Section 2 gives a brief account of Tugan’s business cycle theory, since, as the author maintained, the latter would be organically connected with his disproportionality theory. Section 3 is devoted to Tugan’s analysis of an economic system in the presence of different intersectoral growth rates: unbalanced growth is assured by a traverse along which surplus value migrates to the sector which grows faster. In the concluding section, we maintain that Tugan-Baranowsky comes out as a pioneer in the field of non-proportional economic dynamics.