The dissociative disorders concern both the phenomenal and the cognitive aspects of consciousness. Research on their antecedents suggests that they emerge from the intersubjective context of disorganized attachment, where genetic factors play a secondary role. The characteristic feature of disorganized attachment is the attunement between the quality of the infant's consciousness and the altered consciousness of a caregiver suffering from unresolved traumas and losses. Together with theories from neurobiology (Edelman) and evolutionary anthropology (Tomasello), researches on mirror neurons and empirical studies of early autism, the inquiry on the relationships between disorganized attachment and dissociative disorders suggests that consciousness, rather than being a property of the individual brain, emerges from intersubjectivity. Observations during the psychotherapy session with patients suffering from dissociative disorders illustrate the interpersonal dimension of consciousness.