The ways in which residential aged care staff conceptualize the identities of residents with dementia has significance for how they support them to make decisions and make decisions on their behalf. This article aims to further understand how staff in residential aged care facilities comprehend who residents “are.” Methods: This qualitative study draws on individual and group interview data with aged care staff from two Australian states concerning decision making for individuals with dementia. It identifies themes relevant to how staff refer to identity in relation to such residents. Results: Staff possess disparate ideas about what things comprise residents’ identities and, accordingly, which sources of knowledge are most relevant to learning about residents. Discussion: This article argues for the application of a multidimensional and temporally inclusive understanding of identity by those who provide care to people with dementia.