Functional gastrointestinal disorders (FGIDs) are the most common diagnoses in gastroenterology, characterized by morphologic and physiological abnormalities such as motility disturbance, visceral hypersensitivity, altered mucosal and immune function, altered gut microbiota, and altered central nervous system processing. The Rome Foundation has played a key role in developing diagnostic criteria for FGIDs, leading to the creation of Rome IV, which improves upon Rome III by updating the literature, offering new information on gut microenvironment, gut-brain interactions, pharmacogenomics, and biopsychosocial, gender, and cross-cultural understandings of FGIDs. Rome IV reduces the use of imprecise and stigmatizing terms, uses updated diagnostic algorithms, and incorporates information on the patient illness experience and physiological subgroups or biomarkers. The Rome Foundation's work has helped legitimize FGIDs and advance research and treatment. FGIDs have evolved from a dualistic and reductive perspective to a more comprehensive biopsychosocial model, with the scientific basis for symptom generation shifting from disorders of motility to neurogastroenterology and brain-gut interactions. The Rome Foundation's history began in the late 1980s, when there was little understanding of FGID pathophysiology, no established classification system, and no guidelines for standardized research. The Rome Foundation has since played a pivotal role in operationalizing research and disseminating knowledge on FGIDs. The Rome criteria have been updated to reflect current scientific knowledge, and the new definition of FGIDs is as disorders of gut-brain interaction. Rome IV includes new diagnoses such as narcotic bowel syndrome, opioid-induced constipation, and cannabinoid hyperemesis syndrome, which differ from other FGIDs by having known etiologies. The term "functional" has been used in the past, but it has limitations and is potentially stigmatizing. Rome IV has removed the term "functional" from article titles and diagnoses where possible, and has changed the name of functional abdominal pain syndrome to centrally mediated abdominal pain syndrome. Rome IV also includes new articles and modifications to existing ones, such as the addition of an article on the intestinal microenvironment and the inclusion of pharmacogenomics in the pharmacological aspects of FGIDs. The Rome IV criteria have been revised to include evidence-based thresholds for symptoms and to address the limitations of previous criteria. The Rome IV classification system is based primarily on symptoms rather than physiological criteria, and includes 33 adult and 20 pediatric FGIDs. The Rome IV criteria have been developed through a rigorous process involving data gathering, synthesis, and peer-review. The Rome IV criteria are of particular value for clinical research and pharmaceutical trials, but there are limitations for use in clinical practice, such as the potential exclusion of patients who do not fully meet the criteria but could be treated similarly. The Multidimensional Clinical Profile method is used to teach individualized treatment based on identifying and integrating the multiple components of the symptom experience. The Rome IV criteriaFunctional gastrointestinal disorders (FGIDs) are the most common diagnoses in gastroenterology, characterized by morphologic and physiological abnormalities such as motility disturbance, visceral hypersensitivity, altered mucosal and immune function, altered gut microbiota, and altered central nervous system processing. The Rome Foundation has played a key role in developing diagnostic criteria for FGIDs, leading to the creation of Rome IV, which improves upon Rome III by updating the literature, offering new information on gut microenvironment, gut-brain interactions, pharmacogenomics, and biopsychosocial, gender, and cross-cultural understandings of FGIDs. Rome IV reduces the use of imprecise and stigmatizing terms, uses updated diagnostic algorithms, and incorporates information on the patient illness experience and physiological subgroups or biomarkers. The Rome Foundation's work has helped legitimize FGIDs and advance research and treatment. FGIDs have evolved from a dualistic and reductive perspective to a more comprehensive biopsychosocial model, with the scientific basis for symptom generation shifting from disorders of motility to neurogastroenterology and brain-gut interactions. The Rome Foundation's history began in the late 1980s, when there was little understanding of FGID pathophysiology, no established classification system, and no guidelines for standardized research. The Rome Foundation has since played a pivotal role in operationalizing research and disseminating knowledge on FGIDs. The Rome criteria have been updated to reflect current scientific knowledge, and the new definition of FGIDs is as disorders of gut-brain interaction. Rome IV includes new diagnoses such as narcotic bowel syndrome, opioid-induced constipation, and cannabinoid hyperemesis syndrome, which differ from other FGIDs by having known etiologies. The term "functional" has been used in the past, but it has limitations and is potentially stigmatizing. Rome IV has removed the term "functional" from article titles and diagnoses where possible, and has changed the name of functional abdominal pain syndrome to centrally mediated abdominal pain syndrome. Rome IV also includes new articles and modifications to existing ones, such as the addition of an article on the intestinal microenvironment and the inclusion of pharmacogenomics in the pharmacological aspects of FGIDs. The Rome IV criteria have been revised to include evidence-based thresholds for symptoms and to address the limitations of previous criteria. The Rome IV classification system is based primarily on symptoms rather than physiological criteria, and includes 33 adult and 20 pediatric FGIDs. The Rome IV criteria have been developed through a rigorous process involving data gathering, synthesis, and peer-review. The Rome IV criteria are of particular value for clinical research and pharmaceutical trials, but there are limitations for use in clinical practice, such as the potential exclusion of patients who do not fully meet the criteria but could be treated similarly. The Multidimensional Clinical Profile method is used to teach individualized treatment based on identifying and integrating the multiple components of the symptom experience. The Rome IV criteria