An inquiry was made into the physical and behavioural problems presented by patients admitted to hospital because of dementia. 81 patients were studied over a period of 3 years, and a comparison was made between the 38 with idiopathic (Alzheimer’s) dementia, and the others, most of whom suffered from focal cerebral arteriosclerosis or Parkinson’s disease with dementia. The average age was between 70 and 80 years, and the hospital stay averaged 18–28 months. Nursing difficulties ranged from immobility of the patients on the one hand to wandering on the other, especially in the Alzheimer’s group. Behaviour disturbances, shouting, incontinence and degenerate habits were found in a high proportion, and the incidence of fractures reached 15%. Vascular incidents as complications or causes of death were relatively uncommon; in those who died, the cause was usually infection. The mainstays of treatment were tranquillising drugs, used only when necessary, and in minimal quantities, simple occupational activity, and an awareness by the staff of the high morbidity to which these patients were prone.