The requirement for District Health Authorities to assess the health care needs of their population implies that they must consider how well acute hospital care meets these identified needs. This study, which was conducted in an inner London health district, identified that 123 (14.6%) patients were perceived by medical and/or nursing staff to be inappropriately located in an acute bed. This group was dominated by patients aged 65 years or above, those in general and geriatric medicine, those with a length of stay of 30 days or more, and those with high levels of physical and mental dependency. The main reasons for patients being labelled as 'inappropriate' were the need for non-acute health services (eg rehabilitation, terminal care etc), a need for nursing home places or because of social or housing problems. Five months after identification, the notes of 100 of the 123 inappropriate patients were traced. Retrospective classification of these notes using the more 'objective' Oxford Bed Study Instrument showed that 97 patients were still defined as inappropriate. Details of the length of inappropriate stay were available for 74 patients who accrued 7,519 inappropriate bed days at a cost of 836,547 pounds. These patients are an illustration of the potential failings of current health and social care systems and highlight the need for imaginative care solutions which bridge this divide.