The internal cardioverter defibrillator corrects life-threatening arrhythmias by providing antitachycardia pacing, pacing for bradycardia, and cardioversion or defibrillation shocks. However, there is little warning that the device may fire, which can cause physical, social and psychological problems for the patient. Nurses caring for ICD patients in the community and in hospital need to know what it is like to live with this device, how it works and the implications for other treatments.