This article discusses ethical aspects of ‘terminal sedation’ in relation to end-of-life care. An examination of the literature reveals there are different definitions and explanations of terminal sedation. Some definitions appear compatible with the values of palliative care and nursing, whereas others could arguably be perceived as deserving of the term ‘euthanasia in disguise’. The authors suggest that ‘palliative sedation’ is a more helpful term and argue that, when defined and understood appropriately, it is a defensible and ethical practice. Nurses should be clear about the purpose of their profession, honest about their intentions and respect the autonomy and dignity of the patients for whom they provide care. The doctrine or principle of ‘double effect’ has been put forward to support the practice of terminal sedation. The authors examine this doctrine and caution that nurses and other professions need to approach it critically in relation to terminal sedation. Vignettes are used to illustrate aspects of the discussion.