The first-generation subcutaneous implantable cardioverter defibrillator (S-ICD) effectively detects and terminates induced and spontaneous malignant ventricular arrhythmias with an inappropriate shock rate comparable with that of transvenous defibrillators. The S-ICD is an option for implantable defibrillator candidates who do not require pacing for bradycardia, cardiac resynchronization, or antitachycardia pacing indications. It is recommended for patients with compromised vascular or cardiac access and should be considered in younger patients and those needing a shock-only device. Wider implementation is dependent on randomized clinical trial data showing noninferiority to the transvenous ICD, together with the results of long-term registries.