OBJECTIVE: To explore the role of health care chaplains in providing pastoral care to patients, their families and clinical staff considering decisions to withdraw life support. METHODS: Quantitative data were obtained retrospectively from a survey of 327 Australian health care chaplains (both staff and volunteer chaplains) to initially identify chaplaincy participation in withdrawal-of-life-support issues. Qualitative data were subsequently obtained by in-depth interview of 100 of the surveyed chaplains and thematically coded using the World Health Organization Pastoral Intervention (WHO-PI) codings to explore chaplains' roles. RESULTS: Over half the staff chaplains surveyed (57%) and over a quarter of the volunteer chaplains (28%) indicated that they had been involved with patients or their families in withdrawal-of-life-support decisions. Over a third of staff chaplains (37%) and 16% of volunteer chaplains had assisted clinical staff concerning withdrawal-of-life-support issues. The qualitative data revealed that chaplains were involved with patients, their families and clinical staff at all levels of pastoral intervention, including "pastoral assessment", "pastoral ministry", "pastoral counselling and education" and "pastoral ritual and worship". The specific nature of chaplaincy involvement varied considerably depending on the idiosyncratic issues faced by patients, families and clinical staff. These activities indicated that pastoral care could be provided for the support and benefit of patients, their families and clinical staff facing a complex bioethical issue. CONCLUSIONS: Through a variety of pastoral interventions, some chaplains (mostly staff chaplains) were involved in assisting patients, their families and clinical staff concerning withdrawal-of-life-support issues and thus helped ensure an holistic approach within the health care context. Given this involvement and the future potential benefit for patients, families and clinical staff, there is a need to develop continuing education and research on pastoral care and chaplaincy services.