Electrosurgery is used in the majority of endoscopic therapeutic procedures. An understanding of the fundamental electrosurgical principles and various settings available on electrosurgical units is essential for the safe and effective use of electrosurgery during endoscopy. The aims of these technical guidelines are to: (1) expose physical principles relevant to the understanding of electrosurgery during endoscopy; (2) describe and provide practical recommendations regarding electrosurgical units that are commonly in use; (3) discuss the clinical relevance of technologies recently implemented in newer electrosurgical units; and (4) review factors relevant to commonly performed therapeutic procedures, including polypectomy, sphincterotomy, contact thermal hemostasis, and argon plasma coagulation.