Gastroesophageal reflux disease (GERD) is an important and frequently occurring problem among intellectually disabled individuals (IDI). Early suspicion and recognition of the presence of GERD in IDI is the cornerstone of adequate management of these patients. The prevalence of GERD among institutionalized IDI with an IQ < 50 is about 50%, with 70% of these reflux patients having endoscopically established reflux esophagitis. In case of symptoms as hematemesis, rumination, or dental erosions, there is an increased risk for GERD. GERD has also been shown to be associated with cerebral palsy, an IQ < 35, scoliosis, and the use of anticonvulsant drugs or benzodiazepines. To establish the diagnosis, 24-h pH measurement or endoscopy should be used in all those intellectually disabled individuals in whom GERD clinically is suspected. The efficacy of proton-pump inhibitors (PPIs) in IDI with GERD is indisputable. In IDI, adults as well as children, PPIs are highly effective, independent of the severity of esophagitis. Marked improvement of symptoms and quality of life can be noticed after medical treatment, thereby decreasing the need for surgery in this complicated group of patients.