Achalasia is a rare idiopathic disease, associated with significant morbidity and negative impact on life quality. The disorder is characterized by impairments in the esophageal motility and loss of the lower esophageal sphincter (LES) relaxation. Achalasia symptoms include dysphagia, regurgitations, chest pain, vomiting and weight loss. Diagnosis of achalasia is based on an appropriate clinical presentation and typical findings on complementary tests. These tests include endoscopy showing a dilated esophageal lumen containing fluid or food, High-resolution manometry (HRM) shows evidence of obstruction at the gastro-esophageal junction and motility failure, and barium swallow shows esophageal dilation and distal narrowing. The recent advent of HRM has permitted more precise diagnosis of achalasia and three subtype designations, based on the pattern of esophageal motility disorders, as per the Chicago Classification. Treatment options include: drugs, endoscopic by means of Botox injection or balloon dilation, and the traditional surgery, laparoscopic Heller myotomy (LHM). The new advent in treatment is the novel per-oral endoscopic myotomy (POEM), a less invasive therapy, approaching the traditional LHM. Since the first POEM procedure performed in 2008, massive amounts of evidence are accumulating regarding the high efficacy and safety profiles of POEM, introducing it as an excellent first line treatment. The current review discusses the diagnosis and management of achalasia, with special highlights on the recent progress of HRM and POEM.