From the first decade of the twentieth century until the emergence of Peronism, much of the history of the Argentine labor movement was marked by the stamp of "syndicalism." Hernán Aragón explores it historically in this essay, giving an account of its different variants and mutations. From its explosive appearance as "revolutionary syndicalism", through its turn to increasingly conciliatory positions typical of a reformist current, the book culminates at the moment when syndicalism buries one of its fundamental postulates, political dispensation, playing a key role in the formation of the political organization that will allow Perón's rise to power. the Labour Party. On each of these moments, Critical History of Syndicalism makes a sharp analysis, subjecting the syndicalist strategy to a political critique. Thus, the author demystifies those visions that denied the influence of the old generation of trade unionists as a base of support for the emergence of the movement led by Perón, making a critical evaluation of their practice and ideology and how they collaborated in paving the way for the consolidation of Peronism. The current economic crisis, the deepest since the Great Depression of 1929, will inevitably generate greater social contradictions, once again calling into question the role of trade unions, parties and the political autonomy of the working class. It is these elements that give full validity to the debate that this work takes up.