Abstract : Paedophilia is a paraphilia characterised by behaviour, drives or sexual fantasies that are intense and recurring and that involve children, in a general sense. This sexual deviation is often linked to personal distress, to a significant alteration of personal, family, professional and social life, in a general sense. In our modern Western societies, paedophilia and the perversions associated with it are punishable by law. Paedophilia is a concept that is very ancient, complex and particularly diverse in its many clinical presentations. Its societal impact is very important and contrasts with the real knowledge of this issue among non-specialists, or even among specialists. Based on expert clinical experience gathered at the courts and on an exhaustive review of current literature on the subject, the authors propose an update of the concept of paedophilia. In the first part of this work, the authors will discuss several aspects such as the historical background and the clinical aspects and nosography of paedophilia. This literature review will be accompanied by short clinical vignettes, based on the authors’ clinical experience.