Leave NO vulnerable people behind in SDGs era- from the viewpoints of health insurance and medical treatment, Necessity of health care system to secure emergency treatment for non-Japanese residents without public health insurance., Factors hindering hospitals from accepting foreign patients: our issues and plans, Welfare state, National health insurance system, Immigrants: Political-Administrative analysis on uninsuredness, Securing and enhancing access to health care for undocumented/irregular migrants: Overseas policies and gap-filling practices