The aim of this article is to establish a relationship between the theory of René Kaës on the unconscious alliances (2011) and the structuring of the psyche, using as a tool the dialog text on narcissism by Freud (1914/1996) and on the contract narcissistic (1975) by Piera Aulagnier. We try to understand how the unconscious of another person influences the psychic constitution of the subject, with a preference strongly based on intersubjectivity, as the authors emphasize in the studies pointed out in this article.