When clinicians label a child as having a functional disorder, there is often a pejorative connotation that the symptoms are psychological, imagined, or faked. These symptoms range from chronic abdominal pain to recurrent headaches to fatigue. We say the complaints are functional because we are unable to demonstrate any structural or biochemical abnormality causing them. The degree to which we go searching for these abnormalities varies from case to case and often depends on our own clinical experience, insecurities, and demands of the patient's family. Labeling a child as having a functional complaint can put a tremendous burden on the child and family, because if this concept is presented improperly (as implied above), it can suggest that it is their fault there are symptoms and that if they "got their act together" the symptoms would melt away. Functional gastrointestinal disorders are defined as conditions in which a variable combination of chronic or recurrent gastrointestinal symptoms are present in the absence of demonstrable disease. There may indeed be physiologic abnormalities underlying the symptoms, but at the present time we are unable to detect them. We make a diagnosis based on symptoms, not on demonstrable abnormalities in physical examination or laboratory tests. A number of common pediatric diagnoses fall into this category, including infant regurgitation, chronic nonspecific diarrhea, irritable bowel syndrome, non-ulcer dyspepsia, infant dyschezia, and functional constipation. This paper presents a brief review of our current understanding of each diagnosis and gives suggestions for management.