The book The Accumulation of Capital by Rosa Luxemburg, conceived in order to provide a theoretical basis for the fight against imperialism waged by the left wing of the German Social Democratic Party – and, by extension, of the Second International, was the subject of furious controversial from the moment of its publication in 1913. Our paper deals with the reception of that work within the Second International before the outbreak of the First World War, in the light of the documents in our recent book Discovering Imperialism: Social Democracy to World War I (Brill, 2012). These documents are presented according to their political affiliation, focusing first in the reactions of centrist wing theorists, gathered around Karl Kautsky in Germany and Otto Bauer in Austria, and then in the attitudes of two theorists of the left wing of the Second International: the “tribunista” Anton Pannekoek and the Dutch leader of the Bolshevik wing of the Russian Social Democratic Labour Party, Vladimir Lenin. Our analysis shows that, although the sentence of capital accumulation by the centrist was almost unanimous, acceptance by the left wing was far from universal. In fact, both Pannekoek and Lenin rejected Luxemburg’s theory of imperialism and economic analyzes and adopted a prominent centrist wing spokesman: the Austro-Marxist Rudolf Hilferding. Our work concludes by analyzing the reasons for the theoretical disagreements. ; El libro La acumulación del capital de Rosa Luxemburg, concebido con el fin de proporcionar una base teórica a la lucha contra el imperialismo librada por el ala izquierda del partido socialdemócrata alemán – y, por extensión, de la Segunda Internacional –, fue objeto de furiosas polémicas desde el momento de su publicación en 1913. Nuestra ponencia trata sobre la recepción de dicha obra en el seno de la Segunda Internacional antes del estallido de la Primera Guerra Mundial, a la luz de los documentos recogidos en nuestro reciente libro Discovering Imperialism: Social Democracy to World War I (Brill, ...