The second book in the series “The History of Marxism-Leninism” (the first book was published in 1986) examines the dialectics of the development of Marxism in the last three decades of the 19th century in close connection with the formation of mass workers' socialist parties of the Second International. The book analyzes such classic works of Marxism , such as “Critique of the Gotha Program” by Marx, “Anti-Dühring” and “Dialectics of Nature” by Engels, etc. The further development of dialectical and historical materialism, the theory of socialism, and the Marxist concept of the revolutionary process is considered. Special chapters are devoted to Marxist political economy (volumes II and III of Capital), as well as the views of the founders of Marxism on the features and prospects of Russian society. A significant place in the volume is given to the theoretical activities of the comrades and students of Marx and Engels - Bebel, Kautsky, Lafargue, Liebknecht, Labriola, Mehring, Plekhanov, Blagoev, etc. The development of Marxism is presented in the book as a process of its continuous creative renewal, which includes critical revision theoretical results achieved by Marxist thought at one or another stage of its history.* * *At this point, the publication of the multi-volume “History of Marxism-Leninism” ceased.* * *The second book of the series was published in two parts (the first part - up to the sixth chapter inclusive; reference apparatus – common for two parts at the end of the second part). In this electronic edition, both parts of the book are combined into one file. The composition of the creative team, published at the beginning of the publication, includes lists of both parts of the book. In the paper edition of the book there are significant fragments of text typed in small print. In the electronic edition, these fragments are formatted as quotes.