This article proposes a reconstruction of the Marxian theory of alienation, emphasizing two aspects that have been largely neglected in the vast critical literature on the subject. On the one hand, the eminently practical and material character of the alienation that Marx describes. On the other hand, the frequent references in his work to the human being as a collective subject, as a concrete species and as a real historical society that produces its own life and its own power by transforming nature of which it is part.