IMPORTANCE: Gastroesophageal reflux disease (GERD) is defined by recurrent and troublesome heartburn and regurgitation or GERD-specific complications and affects approximately 20% of the adult population in high-income countries. OBSERVATIONS: GERD can influence patients' health-related quality of life and is associated with an increased risk of esophagitis, esophageal strictures, Barrett esophagus, and esophageal adenocarcinoma. Obesity, tobacco smoking, and genetic predisposition increase the risk of developing GERD. Typical GERD symptoms are often sufficient to determine the diagnosis, but less common symptoms and signs, such as dysphagia and chronic cough, may occur. Patients with typical GERD symptoms can be medicated empirically with a proton pump inhibitor (PPI). Among patients who do not respond to such treatment or if the diagnosis is unclear, endoscopy, esophageal manometry, and esophageal pH monitoring are recommended. Patients with GERD symptoms combined with warning symptoms of malignancy (eg, dysphagia, weight loss, bleeding) and those with other main risk factors for esophageal adenocarcinoma, such as older age, male sex, and obesity, should undergo endoscopy. Lifestyle changes, medication, and surgery are the main treatment options for GERD. Weight loss and smoking cessation are often useful. Medication with a PPI is the most common treatment, and after initial full-dose therapy, which usually is omeprazole 20 mg once daily, the aim is to use the lowest effective dose. Observational studies have suggested several adverse effects after long-term PPI, but these findings need to be confirmed before influencing clinical decision making. Surgery with laparoscopic fundoplication is an invasive treatment alternative in select patients after thorough and objective assessments, particularly if they are young and healthy. Endoscopic and less invasive surgical techniques are emerging, which may reduce the use of long-term PPI and fundoplication, but the long-term safety and efficacy remain to be scientifically established. CONCLUSIONS AND RELEVANCE: The clinical management of GERD influences the lives of many individuals and is responsible for substantial consumption of health care and societal resources. Treatments include lifestyle modification, PPI medication, and laparoscopic fundoplication. New endoscopic and less invasive surgical procedures are evolving. PPI use remains the dominant treatment, but long-term therapy requires follow-up and reevaluation for potential adverse effects.