This paper approaches institutionalized dementia care as a site of societal disposal, valuation, and care for human life. Drawing upon six weeks of ethnographic fieldwork and ten qualitative interviews carried out in a Danish dementia nursing home in 2014, we analyze how nursing home staff, through everyday care, uphold the value of life for residents in severe mental and physical decline. We argue that life's worth is established when residents gain qualities of personhood and agency through substitution processes carried out by staff. Yet the persistent absence of conventional personhood and autonomous agency in residents (i.e. capacities for memory, consciousness, language, and mobility) evokes experiences of ambiguity in staff and relatives of residents. We close the article with a discussion of this ambiguity and the significance of the nursing home as care institution in the welfare state. Dementia care, we propose, is not only about preserving the lives of people with dementia. At stake in the daily care practices around severely disabled residents in the nursing home is the very continuance of the main principles of the welfare society.