The aim of the study was to examine the dimensions and the nature of the deprivations of liberty to which psychiatric patients of 65 years of age and older are exposed. The diagnostic pattern of these patients was also investigated. The case records of 97 elderly patients that had been exposed to a deprivation of liberty during the five year period from 1 October 1989 to 30 September 1994 were reviewed. There were 63 compulsory commitments to the psychiatric department in Ballerup during this period. More elderly patients were committed due to a need for treatment (yellow admission papers) than due to their being dangerous to themselves or other people (red admission papers). There were proportionately more compulsory than voluntary commitments among patients of 65 years of age and over than among patients under the age of 65. Elderly women committed for treatment (yellow admission papers) were deprived of their liberty for a longer period than elderly men committed for the same reasons. The most frequent diagnosis on discharge from the hospital was senile dementia. There is a different pattern of deprivation of liberty among elderly psychiatric patients than among those under the age og 65. The legal aspects surrounding the largest group of elderly compulsory commitments have not yet been satisfactorily clarified.