This article reports on a study exploring the challenges and complexities of caring for a child with cancer no longer responding to curative therapy. The difficulties that health professionals face when initiating and providing palliative care to children with cancer is largely unexplored. A greater understanding of these challenges is needed to inform the development of effective models of care. Participatory group discussions and in-depth interviews were used to explore how health professionals from three disciplines - nursing, medicine and social work - view their role during the shift from cure to palliation. Interviews were tape-recorded and transcribed verbatim. Content and thematic analysis was used to identify themes and important messages in the transcripts. This study illustrates how the trajectory of childhood cancer is characterized by uncertainty, especially following relapse where there is reduced clarity surrounding the child's outcome. Prognostic uncertainty and continued hope for survival make the shift to palliation difficult, raising questions about the applicability of traditional palliative care models for these children and their families. Decision making in this context is complicated by a lack of clarity, uncertainty and continued hope. Shifting the focus of care from cure to palliation is not experienced as a discrete event but rather, as an awareness and acceptance that slowly develops. New models of care that incorporate palliative care throughout the disease trajectory are recommended.