Medical and social data on 980 consecutive admissions to the Medical Department, Aker Hospital, Oslo, were recorded prospectively with emphasis on patients' requirements and the Department's use of available resources. 73% of the admissions were acute, 4% were considered unnecessary. Half were because of chronic illness. Although 88% of the patients' requirements could have been met at a local hospital, 59% were treated in specialized units. 12% were admitted to the day unit at reduced cost for an average stay of three days. 41% of the patients were over 70 years of age, 37% lived alone and 14% needed rehabilitation. A main reason for admission was the patient's inability to take care of him/herself at home, in nearly all cases the main reason being acute illness or deterioration. Therefore many of the patients seemed to need care in an acute geriatric unit. At any one time the reason for 20-25% of the patients being in the department was delay in providing care at home or in a nursing home.