The patient in long-term psychodynamic group psychotherapy is a participant in the work of a laboratory of interpersonal relationships. Each patient has the opportunity to experience his or her problems within the psychotherapy itself. Those problems are the interpersonal manifestations of whatever psychological problems the group member has. In individual therapy, the patient is the focus of concentrated attention by a dedicated individual who attempts to minimize the effect of his or her own agenda. That in itself is an extraordinary state of affairs—one that is encountered in ordinary life rarely, if ever. Perhaps the healthy parent of a newborn attempts to create such a one-sided relationship, but nowhere else in life will the other equivalently ignore his or her own needs and desires. Life is with people, ordinary people who all want to have their own requirements met. That is the situation that is achieved in the psychodynamic therapy group. Consequently, the group member experiences a setting far closer to the one in which he or she lives than is otherwise available in therapy. That immediate experience of collaborating and contending with others to have one's needs met is the hallmark of psychodynamic group psychotherapy and leads ineluctably to the crucial principle that underlies the work of the therapist in leading such a group. The primary principle of technique is to use this microcosm of the interpersonal world—the group—to the fullest extent possible.