Anti-reflux mucosal ablation (ARMA) is a novel and minimally invasive endoscopic approach for managing gastroesophageal reflux disease (GERD). Building upon the principles of anti-reflux mucosectomy (ARMS), ARMA uses targeted mucosal ablation at the gastric cardia to induce scarring and reshape the mucosal flap valve, enhancing its anti-reflux barrier. This chapter focuses on ARMA, its simplified technique, clinical efficacy, safety profile, and its role in bridging the treatment gap for GERD patients who are refractory to proton pump inhibitors (PPIs) or unwilling to undergo surgery. Clinical studies demonstrate its effectiveness in symptom relief, acid exposure reduction, and decreasing dependency on PPIs, making ARMA a promising addition to GERD management.