Infants and children have historically received a weight-based escalating defibrillation dose, commencing at 2J/kg. Researchers are increasingly suggesting that 2J/kg maybe an ineffective initial defibrillation dose. However without a definitive study there has been hesitancy to modify this initial dose. The International Liaison Committee on Resuscitation made a recommendation in 2010 of an initial dose of 2-4 J/Kg, increased from 2 J/Kg. The American Heart Association and the European Resuscitation Councils now have different initial dosing recommendations for children. The ERC advocates 4J/kg as the initial dose without escalation for subsequent shocks, while the AHA recommends 2-4 J/Kg, increasing to ≥ 4 J/Kg with subsequent shocks up to adult dose. The difficulty of finding a dose based on robust evidence continues to provide a stimulus for research to better define the best defibrillation energy dose for children.