Functional Gastrointestinal Disorders (FGIDs) are defined as a variable combination of chronic or recurrent gastrointestinal symptoms, age dependent, not explained by structural or biochemical abnormalities. Recurrent gastrointestinal disorders, especially abdominal pain, are one of the most common reasons for medical consultation among children and adolescents. A population-based study demonstrated that 28-46% of school age children complain of abdominal pain each week. Only in 10% of the cases an organic cause can be identified, while most of the children and adolescents who present these symptoms have a functional disorder without any evidence of disease. FGIDs significantly influence the quality of life of affected children and have a big social impact related to socialization, school absences and could have long-term psychological implications. A complete understanding of the pathophysiology of FGIDs remains elusive. FGIDs are a multifactorial condition and diverse pathophysiologic mechanisms appear to contribute to them, including altered motility, visceral hyperalgesia, brain-gut disturbances, genetic and environmental factors, and psychosocial upsets, among others. In 2006 the new version of the Questionnaire on Pediatric Gastrointestinal Symptoms (QPGS) based on Rome III Criteria (QPGS-RIII) was created, in order to validate such criteria and to facilitate the diagnosis of FGDIs in children and adolescents. The Italian translation of the QPGS-RIII has been realized by our research group to spread a valid and universal method to screen the children potentially affected by FGDIs.