Functional gastrointestinal disorders are collections of symptoms attributable to the gastrointestinal tract in the absence of mucosal, structural, or biochemical disease. The two most common disorders, irritable bowel syndrome and functional dyspepsia, have common etiopathogenetic features, notably psychosocial disturbances, dysmotility, heightened sensitivity, and, possibly, an association with a postinfective state. The third condition is constipation, in which transit disorders and abnormal evacuation represent disturbances of function that are amenable to therapy. This review is an update of the control mechanisms, pathophysiology, investigation, and potential pharmacotherapies of these disorders. Serotonergic and adrenergic agents and neurotrophic factors are among the novel approaches that may have a significant impact on these disorders.