The article presents the case of a young patient with a severe dissociative pa-thology, in the care of a Public Mental Health Center and describes the specific characteristics of the setting during the treatment. The patient was both attending the Day Care Center daily and following and individual psychotherapy, that dou-bled in two distinct settings. Starting from this peculiar form of multiple setting, some reflection are proposed, on the presence, in the professional practice, of "an-cestral" forms of multiple settings and on the possibility that these conditions could be, in some cases, opportunities to let some blind areas to emerge.
Keywords: Setting, dissociation, trauma, analytic third, transfert