An instrument was developed to study the use of hospital beds and discharge arrangements of a cohort of 847 admissions to the John Radcliffe Hospital, Oxford, for a three week period during February-March 1986. For only 38% of bed days were patients considered to have medical, nursing, or life support reasons for requiring a provincial teaching hospital bed. The requirements for a bed in the hospital decreased with the patient's age and length of stay in hospital. For only a tenth of patients was the general practitioner concerned in discussions with hospital staff about the patient's discharge and less than one third of patients had been given more than 24 hours' notice of discharge.Several features might increase the proportion of bed days that are occupied by patients with positive reasons for being in hospital. Among these are an increased frequency of ward rounds by consultants, or delegating discharge decisions by consultants to other staff; providing diagnostic related protocols for planning the length of stay in hospital; planned discharges; and providing liaison nurses to help with communication with primary care staff.