Naikan therapy is a method of psychotherapy that was created based on original Japanese culture, as was Morita therapy. The method of treatment, and relationship between the doctor and patient in Naikan therapy are different from those in Western therapy in that they are based on oriental thought. Furthermore, Naikan therapy has not be used in clinical practice in Japan because most Japanese psychotherapy practices are based on the theories and techniques introduced from the West. There are two reasons for this. First, the mechanism of the therapeutic effects of Naikan therapy has not be sufficiently explained. We have to verbalize the method of treatment in Naikan therapy, and the relationship between the doctor and patient, as well as what the mechanism is and what influence it has on patients in order for doctors to understand. Second, the training system for Naikan therapy was only recently established. It is necessary for doctors to relearn psychotherapy methods. We plan to implement the Naikan training system and accreditation system from this year. We hope that these systems will help doctors understand and use Naikan therapy.
 The present Naikan therapy is widely applied not only as cognitive behavioral therapy (CBT) or psychosocial therapy, but also in psychosomatic medicine and counselling. Currently, Naikan therapy is considered to have common factors with mindfulness. Outside of Japan, Naikan therapy has become recognized and used beyond the medical field. We hope that Naikan therapy will spread in Japan.
 <Author's abstract>