Abstract
Achalasia is progressive neurodegenerative disorder of the esophagus, resulting in uncoordinated esophageal motility and failure of lower esophageal sphincter relaxation, leading to impaired swallowing. Surgical myotomy of the lower esophageal sphincter, either open or minimally invasive, has been a standard of care for the past several decades. Recently, new procedure-peroral endoscopic myotomy (POEM) has been introduced into clinical practice. This procedure accomplishes the same objective of controlled myotomy only via endoscopic approach. In the current chapter authors review the present state, clinical applications, outcomes and future directions of the POEM procedure.