Achalasia is a rare esophageal motility disorder caused by impaired relaxation of the lower esophageal sphincter (LES) and loss of esophageal peristalsis, leading to dysphagia and regurgitation. Though the cause is unknown, autoimmune or infectious factors are suspected. It typically affects adults aged 30–60 and is diagnosed using endoscopy, barium esophagram, and high-resolution manometry (HRM). HRM is the gold standard for diagnosing achalasiaAchalasia, providing pressure measurements throughout the esophagus and enabling classification into three subtypes. Additional testing, like FLIPFLIP and timed barium esophagramTimed barium esophagram, may help in inconclusive cases. Treatments aim to reduce LES pressure and improve esophageal emptying. Options include medications, botulinum toxin injections, pneumatic dilation (PD)Pneumatic dilation (PD), laparoscopic Heller myotomy (LHM), and per-oral endoscopic myotomy (POEM)Per-oral endoscopic myotomy (POEM). While drugs and botulinum toxin offer short-term relief, PD and myotomy provide longer-lasting effects. POEM is especially effective across all subtypes, including Type III, but is associated with higher rates of gastroesophageal reflux compared to LHM. Recent studies suggest POEM may offer superior outcomes, but treatment should be tailored based on achalasiaAchalasia subtype and patient condition. Accurate diagnosis and individualized therapy are key to improving symptoms and long-term outcomes.