Cardiopulmonary resuscitation is frequently performed on patients who, in retrospect, had a very low chance of survival. This is because all patients are ‘For cardiopulmonary resuscitation’ on admission to hospital by default, and delays occur before cardiopulmonary resuscitation can be ‘de-prescribed’. This article reviews the nature of potential harms caused by futile cardiopulmonary resuscitation, the reasons why de-prescription may be delayed, recent legal judgements relevant to timely do not attempt cardiopulmonary resuscitation decision making, and the possible detrimental effects of do (...) not attempt cardiopulmonary resuscitation discussions on end of life care. The moral and operational feasibility of a model in which informed consent must be obtained before cardiopulmonary resuscitation is attempted in some patient groups is then explored. (shrink)