Psychiatric healthcare services in Japan demand continuous improvement to ensure quality care. Psychiatric nurse administrators and managers greatly influence the quality of services. To improve treatment, the following are considered necessary: clarification of service goal, proper assessment of treatment outcome, shortening of hospitalization, patient-centered care, establishment of trust relationships based on open communication with patients, and effective interdisciplinary teamwork. Additionally, administrators and managers must evaluate the clinical competence of individual nurses and appropriately assign them, especially when personnel shortage is an issue. Furthermore, in collaboration with other healthcare professionals, nurse managers must provide optimal care by setting goals of psychiatric services for patients in acute, sub-acute, or convalescent phases. This article presents the roles of nurse administrators and managers in improving the quality of Japanese psychiatric healthcare services. J. Med. Invest. 58: 1-10, February, 2011