BackgroundAdvance care planning (ACP) is a way of applying modern medicine to the principle of patient autonomy and ensuring that patients receive medical care that is consistent with their values, goals and preferences. Robust evidence supports the benefits of ACP, but it remains an underutilized resource in most countries. This paper goes from the naïve point of view, and seeks to identify the barriers and facilitators to implementation in unfamiliarized contexts and in a whole system approach involving the clinical, institutional and policy level to improve the implementation of ACP.MethodsQualitative interviews were chosen to enable an explorative, flexible design. Qualitative interviews were conducted with 40 health care professionals and chief physicians in hospitals and in municipalities. The thematic analysis was done following Braun and Clarke’s strategy for thematic analysis.ResultsThe main reported barriers were the lack of time and space, a lack of culture and leadership legitimizing ACP, lack of common communication systems, and unclear responsibility about who should initiate, resulting in missed opportunities and overtreatment. Policy development, public and professional education, and standardization of documentation were reported as key to facilitate ACP and build trust across the health care system.ConclusionsProgressively changing the education of health professionals and the clinical culture are major efforts that need to be tackled to implement ACP in unfamiliarized contexts, particularly in contexts where patient's wishes are not legally binding. This will need to be tackled through rectifying the misconception that ACP is only about death, and providing practical training for health professionals, as well as developing policies and legislation on how to include patients and caregivers in the planning of care.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12877-023-04060-4.