Background: Since people with advanced dementia are usually not able to make complex decisions, it is usually the family caregivers, as proxies, who have to decide on treatments and their termination. However, these decisions are difficult for the caregivers to make, as they are often inadequately informed and cannot properly assess the consequences; moreover, they are concerned about harming the sick person. We aimed to first develop an informative booklet about palliative care issues for caregivers of people with advanced dementia. Secondly, we aimed to investigate a change in family caregivers' knowledge regarding palliative care issues and caregivers' involvement in medical and care decisions before and after studying this booklet. Methods: A first version of the booklet was drafted by an experienced psychiatrist and palliative care specialist based on existing booklets and guidelines; necessary cultural adaptions were taken into consideration. A nominal group process was conducted to develop the informative guide. In order to investigate the acceptance of the booklet and the possibility to implement it, 38 patient-caregiver dyads were recruited, and caregivers were interviewed both before receiving the booklet and after 3 months of receiving the booklet. Results: Experts from various disciplines collaborated on a German booklet for family caregivers of people with advanced dementia as an information aid regarding issues of palliative care. The subsequent test showed that all caregivers had experienced a personal benefit from the booklet. Caregivers had a significant gain of knowledge after provision of the booklet. A large proportion of caregivers who had not previously considered and/or discussed medical topics reported that they had done so within 3 months after obtaining the booklet, or planned to do so in the near future. Conclusions: The caregivers valued the comprehensible, concise and well-structured information guide on palliative care issues in advanced dementia. They agreed it increases knowledge and prompts decision making and therefore should be developed in many languages and disseminated among family caregivers of people with dementia. Trial registration: Clinicaltrial.gov, NCT03548142. Retrospectively registered 7 June 2018.