It is necessary to study the containing function of the analyst in the establishment of the setting in psychoanalytical work with children and adults. Beyond the material organization of the setting (the deci­sion as to the day, hour of the sessions, the frequency of the sessions, the payment..), what counts most are the psychical qualities of the psychoanalyst. His (or her) capacity for "reverie" and his psychical qualities serve to sustain and contain the patient's chaotic processes. If the psychoanalyst works with a child, he should be able to help him to develop his thoughts and express them verbally. Bion and ot­her psychoanalysts like Ferro placed psychoanalytical relationship in an interactive field where the analysis of counter-transference of the psychoanalyst is of great importance and use. Thus the psychoanaly­tical encounter is an encounter between two psyches, two unconscio­us, and two infantile.