Located in Saku City, Nagano Prefecture, Mitsui Clinic is a medical facility offering comprehensive healthcare services ranging from outpatient care to hospitalization and home-visit medical care, with a primary focus on internal medicine. The clinic maintains a cooperative relationship with local long-term care facilities—Silver Land Mitsui, Saku Fukujuen, and Sakudaira Ai no Sato—and serves as a partner hospital capable of responding to emergencies for facility residents. The clinic emphasizes health checkups and comprehensive medical screenings, offering optional examinations including brain screening, bone density measurement, and lung cancer CT scans, as well as shingles vaccination. Orthopedic specialist outpatient services are available on the 2nd and 4th Saturday mornings. The facility features barrier-free access and a parking lot, creating an accessible environment for elderly patients and those with physical disabilities. The clinic also supports online eligibility verification using the Individual Number Health Insurance Card, striving to provide high-quality medical care through appropriate acquisition and utilization of medical information.