Sudden cardiac death (SCD) accounts for 230,000 to 350,000 deaths per year in the United States. While many who suffer SCD possess underlying structural heart disease, inherited arrhythmia syndromes are also important contributors to SCD. In patients without structural heart disease, inherited arrhythmia syndromes are identified in >50% of the remaining patients. In this review, we will focus on the presentation and management of three major inherited syndromes that lead to SCD in patients without structural heart disease: long QT syndrome (LQTS), Brugada syndrome, and catecholaminergic polymorphic ventricular tachycardia (CPVT). All these syndromes can present in patients who are asymptomatic or, at the other extreme, with syncope and even SCD. LQTS syndrome and Brugada are the most common inherited arrhythmogenic syndromes, while CPVT is much rarer. Determining which patients need pharmacologic treatment and those who would benefit from more aggressive treatment such as sympathectomies and implantable defibrillators is not always clear. (C) 2019 Published by Elsevier Inc.