Objectives:: Recent research has demonstrated the challenges to self-identity associated with dementia, and the importance of maintaining involvement in decision-making while adjusting to changes in role and lifestyle. This study aimed to understand the lived experiences of couples living with dementia, with respect to healthcare, lifestyle, and “everyday” decision-making. Design:: Semi-structured qualitative interviews using Interpretative Phenomenological Analysis as the methodological approach. Setting:: Community and residential care settings in Australia. Participants:: Twenty eight participants who self-identified as being in a close and continuing relationship (N = 13 people with dementia, N = 15 spouse partners). Nine couples were interviewed together. Results:: Participants described a spectrum of decision-making approaches (independent, joint, supported, and substituted), with these approaches often intertwining in everyday life. Couples’ approaches to decision-making were influenced by “decisional,” “individual,” “relational,” and “external” factors. The overarching themes of “knowing and being known,” “maintaining and re-defining couplehood” and “relational decision-making,” are used to interpret these experiences. The spousal relationship provided an important context for decision-making, with couples expressing a history and ongoing preference for joint decision-making, as an integral part of their experience of couplehood. However, the progressive impairments associated with dementia presented challenges to maintaining joint decision-making and mutuality in the relationship. Conclusions:: This study illustrates relational perspectives on decision-making in couples with dementia. Post-diagnostic support, education resources, proactive dyadic interventions, and assistance for spouse care partners may facilitate more productive attempts at joint decision-making by couples living with dementia.