Pierre Janet (1859–1947) regarded the treatment of his patient Irène as one of his most important case histories; as such he often returned to this case in his later publications and lectures, and a number of subsequent authors have likewise paid attention to it. Regarded before as a paradigm for traumatic memory, the case highlights the existence of trauma-related dissociative amnesia and hypermnesia: in his view, hallmarks of hysteria, i.e., trauma-related dissociation of the personality. Irène developed these symptoms following the death of her mother which had traumatized her. Her amnesia alternated with episode in which she re-enacted the dramatic night and subsequently had amnesia for this re-enactment. She showed intense phobic behavior against remembering the traumatic loss but could eventually overcome this phobia. Janet understood this phobia as a manifestation of her inability to adapt to the consequences of the death of her mother. Also important for current understanding is his subsequent emphasis on the principle of non-realization as the major characteristic of trauma-induced dissociation of the personality; hence, this case can be regarded as a paradigm for non-realization, the core of trauma-related disorders. However, when the formerly traumatic memory has been integrated in the personality and thus realization has taken place, the patient may still be unable to adjust to certain life-situations, as in the case of Irène. This invites discussion as to what the nature of this inability was, hysteria (dissociation) or psychastenia, as both would need different treatment approaches.