Supervision is a useful instrument in psychodynamic psychotherapy as well as in a multi-disciplinary teamwork. Precondition is a confidential setting in which the trainee is able to open him/herself in the relationship to his/her supervisor. Institutional conditions and rules as well as the personal background and professional experience of the trainee play an important role. The specific interest of the authors is the phenomenon of what happens within the trainee-supervisor-relationship, in particular the mirror processes: In general, the patient’s emotions, wishes, fantasies may induce in the therapist specific reactions which psychoanalysts call “counter-transference”. These processes are both conscious and unconscious. The counter-transference feelings can be used in a constructive way as important information about the actual state of the patient’s feelings or can deliver hints to relationship experiences in his life history. These phenomena may take place between patient and psychotherapist as well as between therapist and supervisor. A short empirical questionnaire has been applied to trainees in psychodynamic training to give short examples. The results illustrate that the trainees could be sensibilized for these mirror processes in a cognitive and emotional manner and were able to continue their psychotherapeutic work with deeper understanding for their patients.