Abstract Background: The ongoing national transition in Swedish healthcare towards Integrated Person-centered Care (IPC) [Nära vård] can lead to continuous, seamless, and personalized support for individuals with severe illness, aligning with the core principles of palliative care. Respecting the ill person’s unique circumstances, needs, and preferences also involves addressing the family member’s needs. Facing life-threatening illnesses affects families emotionally and psychosocially, but there are limited psychosocial interventions available. The Family Talk Intervention (FTI), based on psychoeducation, narrative, and dialogical methods, shows promising results. Assessing FTI's implementation sustainability helps ensure families' access to psychosocial and thus address important gaps within an IPC [Nära vård] approach.   Aim: This study explores how healthcare professionals (HCPs) perceive contextual factors influencing the sustainability of FTI after implementation, particularly when a parent with children or youths faces a life-threatening illness.  Method: Fifteen HCPs (13 hospital social workers and two registered nurses) working in specialized palliative homecare services or advanced cancer care were trained in FTI before offering it to families.  After a medium of 18 months, focus groups or individual interviews were conducted. Data was analyzed using conventional qualitative content analysis.  Results: HCPs identified various factors affecting the sustainability of FTI. First, trying to prioritize FTI and coordinate families was complex due to resource constraints, such as a lack of time. Secondly, working without FTI-educated colleagues hampered sustainability as the HCPs using FTI felt isolated, especially when managers and team members showed little support. Thirdly, the satisfaction of seeing families become stronger contributed to a receptiveness for change, provided fulfillment and motivation to continue using FTI, despite contextual challenges. Significance of the Results: This study shows that organizational support, resources, and individual factors such as receptiveness for change are crucial for intervention sustainability, as the positive impact motivates continuous use of an intervention despite challenges.