The prevalence of dementia will continue to increase with the ageing of the population. Many people living with dementia will reach a stage where surrogate decision-makers-mostly family carers-will need to make a range of decisions on their behalf. The aim of this study was to learn from surrogate decision-makers how they can be most effectively supported in this role. The study employed a qualitative design using semi-structured face-to-face or telephone interviews with a purposive sample of 34 surrogate decision-makers of people living with dementia. Transcripts of participant interviews were reviewed using a thematic approach to analysis. Four main themes were identified from this analysis: needing greater community awareness of dementia and its impact; intervening early in cognitive decline; relying on health professionals for ongoing support; and seeking and using support from wherever is relevant for each person. Based on this analysis and a review of the literature, we propose a wholistic set of recommendations for the support of surrogate decision-makers. Healthcare professionals need to help family carers understand the likely trajectory of dementia, including the significance of surrogate decision-making. They can support the person living with dementia and their surrogates to undertake advance care planning and they can act as empathic guides during this process. Health and community care organisations need to provide a "key worker" model wherever possible so that the person living with dementia and their surrogate decision-maker do not have to seek support from multiple staff members or organisations. Carer support programmes can routinely include information and resources about surrogate decision-making. Community and government organisations can help people prepare for the possibility of becoming surrogate decision-makers by promoting a greater public awareness and understanding of both dementia and advance care planning.