This issue of Cardiac Electrophysiology Clinics, Guest Edited by Drs. Jason Bradfield and Kalyanam Shivkumar, is dedicated to Epicardial Interventions in Electrophysiology. This is one of four issues selected each year by the series Consulting Editors, Ranjan K. Thakur and Andrea Natale. Topics include, but are not limited to, Anatomy of the Pericardial Space, Techniques for Percutaneous Access, Peri-operative Imaging to Guide Epicardial Mapping and Ablation, Epicardial Ablation of Idiopathic Ventricular Tachycardia, Epicardial Ablation of Ischemic Ventricular Tachycardia, Epicardial Ablation of Non-ischemic Ventricular Tachycardia, Epicardial Ablation of Arrhythmogenic Right Ventricular Cardiomyopathy, Epicardial Ablation of Ventricular Arrhythmia secondary to Brugada Syndrome, Epicardial Ablation of Supraventricular Tachycardia, Epicardial Ablation of Atrial Fibrillation, Hybrid Surgical Epicardial Ablation, Epicardial Ablation via the Arterial and Venous System, Epicardial Ablation Biophysics and novel Radiofrequency Energy Delivery Techniques, Epicardial Ablation Complications, and The Future of Epicardial Interventions.