In recent years, much evidence and experiences have been accumulated regarding clinical research and practical initiatives for First Episode Psychosis (FEP) and at-risk mental state (ARMS), the state of being at risk for FEP. Overseas, multiple guidelines have been put forth regarding early stage of psychosis including FEP and ARMS. In Japan as well, the "Treatment Plans and Implementation for Early Psychosis: Preliminary Guidance 2017" has been released as a research project of the Japan Agency for Medical Research and Development (AMED). This manuscript explains a psychosocial approach to FEP and ARMS, and the related guidance for their management. For both FEP and ARMS, a psychosocial approach is considered the nucleus of interventional measures. It is essential to select an appropriate intervention method, from the perspective of long-term improvement in the prognosis, after comprehensively evaluating each particular case. During the introduction of treatment with FEP, it is necessary to pay careful attention to establish and maintain a therapeutic alliance. A whole-person, comprehensive assessment is important. An intervention which understands the basic needs of the patient, such as work, education, living situation, interpersonal relationships, and health, and is able to meet such needs is recommended. Regarding ARMS, it is recommended to select a treatment method ranging from a low-intensity, non-specific approach to a high-intensity, specific approach and, if necessary, to perform such selection in a step-by-step manner, upon understanding the high level of clinical heterogeneity. We also strive to provide standard treatment for comorbid symptoms and psychiatric conditions. FEP and ARMS are different clinical stages and have different characteristics. It is necessary to provide appropriate intervention according to the clinical stage.
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