Between March and November, the Oregon Public Health Division was notified of three outbreaks of Norovirus gastroenteritis in a long-term residential treatment facility. Patients and staff had been ill. Person-to-person transmission was suggested by a prolonged and dispersed epidemic curve and lack of illness in some areas of the facility, even though all areas of the facility were served by one central kitchen. Inadequate hygiene and lapses in infection control were noted.