The historical-critical edition of Max Weber's works presents the previously unpublished manuscripts of his lectures on the history of the labor movement given in 1895 in Freiburg and in 1898 in Heidelberg. His lectures offer an impression of his immense knowledge not only in social and economic history since the Roman Empire but also in the political organizations of the modern working classes all over Europe. He also discusses the underlying socialist theories, especially those of Karl Marx. Again, Weber has chosen the comparative approach so important for contemporary research on social and political history. The introduction and the editorial reports as well as a bibliography of the works used by Max Weber, an index of the persons mentioned and a glossary enable the reader to understand his lectures written in the keywords and short sentences typical also for Weber's other lectures.