The decision to withdraw or withhold life support for critically ill patients with no hope of survival is well established and widely accepted. The decision not to treat should be made by more than one doctor, and should be documented in each patient's file. Patients with a bad but not hopeless prognosis should not be weighed against other patients awaiting treatment. Relatives should be fully informed, but should not participate in the formal decision. The reasons and circumstances under which life support can be withheld or withdrawn should be examined further.