The sea-change in our understanding of neurobiology, infant research, and interpersonal/relational psychology over the past two decades makes clear that we are first and foremost a relational species. This finding has massive implications for the relational processes involved in teaching and supervising psychotherapy. Clinical theory and technique can be taught didactically. But relationship can only be learned through careful attention to the supervisory encounter itself. This advanced text surveys the psychodynamic and relational processes involved in psychotherapy and supervision.