ObjectiveThe purpose of this article is to highlight the imprint of the parentification process in a patient in the context of a four-year psychoanalytic psychotherapy, through the analysis of the parentification process in its intrapsychic, intersubjective, and transsubjective dimensions. MethodAfter the end of the therapy, the psychotherapist returns to the material, which involved a patient who presented a depressive disorder and a parentification process during their childhood. We analyzed different themes related to parentification: infantile history, parental imagos, identifying dynamics, parental couple and conjugality, siblings, family functioning, choice of professional career and the relationship to work, and finally, a possible intergenerational or transgenerational transmission of parentification. ResultsWe observed changes to the patient's subjective suffering: better insight, changes in parental imagos, and also changes in the relationship with others (partner and children) as a consequence of an elaborative process around her parentification. In this case, parentification appears as a response to the traumatic infantile parental perception, as a defensive organization, as a survival solution organized around the symbiotic relationship between the child and the sick parent and, later, in relationships of great dependence with her spouse or her children. Throughout the psychotherapy process we observed: a childhood story marked by a generational reversal, an invasive parental imago, narcissistic identificatory dynamics, a parental couple characterized by dysfunctional conjugality, a special place in her siblings, a familial functioning marked by confusion between roles and generations, a professional choice in the field of care, a potential intergenerational or transgenerational transmission of parentification, and finally a dysfunctional parenthood over several generations. The narcissistic dimension of parentification observed in this patient seems to be linked to the omnipotent position vis-à-vis her “failed” parents, which activates a megalomaniacal narcissism and a heroic masochism. DiscussionFor the psychotherapist, the method of treatment and the method of research overlap. The work of writing this case of psychoanalytical psychotherapy allows for new reflections in its aftermath, other elaborations on the material of the sessions, and a tridimensional exploration of the process of parentification: intrapsychic, intersubjective, and transubjective. ConclusionWe underscore the contribution of the clinical elements revealed by the analysis of the transfer/counter-transference dynamics in the process of deparentification.