In this article we consider the Lacanian theory of trauma, with the aim of demonstrating which of Freud's theories Lacan sought to build on and develop in his own model. This approach highlights the continuity, as well as the divergences, between Lacanian psychoanalysis and the Freudian model of trauma. Approaching Lacanian psychoanalysis through the concept of trauma reveals how his theories did not focus only on the subject as determined by the register of language. Rather, Lacanian psychoanalysis emphasises the intimate relationship between the unconscious and the sexual. The Lacanian model of trauma is also of interest for clinical practice, since it provides a better understanding of the Lacanian concept of ‘structure’. This is a concept that considers the impact of events experienced on the psychic functioning of the subject. It can guide the analytical listening during therapeutic work with patients. Aside from its clinical relevance, approaching Lacan's work through trauma makes it possible to clarify the fundamental difference between psychoanalysis and contemporary nosographic approaches to the treatment of trauma, and aetiology in psychopathology.