The esophagus is a muscular tube placed behind the trachea and in front of the thoracic vertebrae. It extends from the pharynx through the thoracic cavity and the diaphragm to the abdominal cavity where it joins with the stomach. The esophageal wall consists of the same layers as the rest of the gastrointestinal tract- mucous membrane, submucous layer, muscularis propria and adventitia except in the most distal part where the esophagus is encased in serosa. The main role of the esophagus is to quickly transport food from the pharynx to the stomach, so its motions are organized in accordance with it. The esophagus physiologically manifests two types of peristaltic motions- primary peristalsis and secondary peristalsis. Primary peristalsis is the continuation of the peristaltic wave which rises in the pharynx during the pharyngeal phase of swallowing. The peristaltic wave traverses the path from the pharynx to the stomach in 8 to 10 seconds. If the primary peristaltic wave fails to move all the swallowed food that entered the esophagus, secondary peristaltic waves generate as a response to the esophageal wall distending. Lower esophageal sphincter is responsible for coordinating the passage of the swallowed food and for ventilating gastric gases. Also, it plays a role in preventing gastric reflux which can potentially damage esophageal mucous membrane. Esophageal manometry is a technique which is useful in evaluating esophageal motility and pressurization. The newest variant of this concept, high resolution manometry, is today widely in use. Each HRM catheter has 36 sensors placed in 1 cm intervals longitudinally and radially, spanning 35 cm in length. Each sensor measures the pressure from 12 different locations in its circumference and generates an average score with it. This way, the technique allows a simultaneous pressure measurement from the pharynx, the upper esophageal sphincter, the esophageal body, the lower esophageal sphincter to the proximal part of the stomach. The most common indication for the esophageal HRM is a further evaluation of the unobstructed dysphagia in patients with persisting symptoms. Other common indications include chest pain 22 of non-cardiac origin, gastroesophageal reflux disease and some systemic diseases which can affect striated, smooth muscle tissue or autonomous nerve system. In order to ease and facilitate the interpretation of esophageal HRM in clnical diagnostics, a work group consisting of various experts developed an algorhythm called The Chicago Classification of esophageal motility. The work group published several publications which defined fundamental measurements and criteria for interpreting esophageal pressure topography.