This article focuses on implantable cardioverter-defibrillator (ICD) therapy in the child/adolescent who is predisposed to sudden cardiac death because of an underlying channelopathy. As such, the primary channelopathies are reviewed briefly. Next, the history of the ICD device and the technological advancements that have enabled its use in pediatrics are discussed. Finally, the clinical experience with ICDs in the young is summarized and general indications for device therapy in young patients who have a channelopathy are provided.