Patients who are in the last few days of life are often too frail to take oral fluids and nutrition. This may be due entirely to the natural history of their disease, although the use of sedative drugs for symptom relief may contribute to a reduced level of consciousness and thus a reduced oral intake. Rehydration with intravenous (i.v.) fluids is the usual response in acute care settings, whereas the hospice movement has often argued against this approach. The issues are complex and involve not only physical, psychological and social concerns, but also ethical dilemmas. A review of the literature gives conflicting reports of the physical discomfort that may be attributed to dehydration in dying patients. There are many confounding variables, including the concomitant use of antisecretory drugs, mouth breathing and oral infection. It remains unproven whether i.v. fluids offer symptomatic relief in this situation. Hospice doctors are concerned that the use of i.v. fluids gives confusing messages to relatives about the role of medical intervention at this stage in a patient's illness. A drip may cause a physical barrier between a patient and their loved one at this important time. The use of other methods of fluid replacement are discussed. In the absence of definitive research in this area, the balance of the burdens and benefits of such treatment remains subjective. The prime goal of any treatment in terminal care should be the comfort of the patient. Decisions should be made on an individual basis, involving both patients and their carers wherever possible. Prolonging life in such circumstances is of secondary concern and i.v. fluids given in this context may be futile. The ethical dilemmas of withholding and withdrawing medical treatment in addition to those of conducting research in this area are discussed.