Individuals and societies have interacted with people with dementia in different ways for as long as the condition has existed. Sometimes this has involved support; sometimes exploitation; and sometimes something in between. What sets the contemporary context apart is that, since the coming into force of the United Nations Convention on the Rights of Persons with Disabilities in 2008 (United Nations, 2006), supported decision-making has assumed a formal legal dimension, one which has been adopted in different ways across different jurisdictions. This article explores forms of supported decision-making through a dementia-centred lens, looking at the benefits of supported decision-making in dementia but also identifying conceptual and practical challenges. It argues that for people with dementia, the availability of supported decision-making offers a legal choice; a way of maintaining some degree of control for as long as possible. However, the specific challenges need to be appreciated. The article compares two legislative frameworks: the Representation Agreement Act 2000 in British Columbia and the Assisted Decision-Making (Capacity) Act 2015 in Ireland, both of which show the complexities involved in developing legislation in this arena.