Located in Saku City, Nagano Prefecture, Mitsui Clinic operates as an internal medicine clinic offering diverse medical services including outpatient care, inpatient treatment, home visits, and comprehensive health screenings. In addition to English language support, the clinic provides parking and barrier-free accessibility, demonstrating consideration for patient accessibility. Regarding medical services, orthopedic specialist examinations are conducted on the 2nd and 4th Saturday afternoons, and shingles vaccination is available by appointment. Comprehensive health screenings include optional tests such as brain scans, bone density measurements, and lung cancer CT scans. The clinic has established a collaborative system with regional long-term care insurance facilities including Silver Land Mitsui, Saku Fukujuen, and Saku-daira Aisato, and plays a role in responding to sudden changes in condition of patients recuperating at these facilities.