The National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB), established by the Ministry of Health, Labour and Welfare in 2008, has collected health data since 2009. Initially for optimizing medical expenses, its use has since expanded for research. In 2021, discussions included broadening data collection (like residence and income info), linking with other public databases (e.g., death certificates), and enhancing convenience through cloud computing. By December 2022, efforts to link with nursing care databases and death certificates were underway. The vision is to connect diverse public data like vaccines, school health checks, and municipal health exams to the NDB, thus expanding "life course data" uses. The 2023 Next Generation Medical Infrastructure Act emphasizes using pseudonymized medical data, linking with public databases, and promoting medical information use. This means researchers can soon analyze comprehensive medical data using NDB and other sources. I'll discuss the medium and long-term prospects of these developments.