With the rapid changing of the social structure, the possibility and limitations of the principal psychiatrist cooperation in the workplace need to be considered. A principal psychiatrist treats patients from the viewpoint of "illness", while the workplace treats patients from the viewpoint of "caseness" with a consideration of the balance between the obligation of security and risk management. The principal psychiatrist has rights to prescribe or write a medical certificate; on the other hand, an occupational physician orders workers and the workplace to create appropriate working conditions in accordance with the relevant and various laws, guidelines, or guidance. The principal psychiatrist can treat "illness" associated with mental health disorders in the workplace, but there are limitations for them to intervene in the workplace. It is important for principal psychiatrists to first understand that occupational health staff including occupational physicians have different standpoints and criteria for judgment, and they must cooperate with the workplace by means of national guidelines or guidance, so that workers with mental health disorders can work while maximizing health.
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