About 4% of consultations in general practice involve patients with upper gastrointestinal complaints. Evidence of peptic ulcer disease is identified in only 20-30% of the patients. No organic explanation of the symptoms is found using endoscopy in 20-50%; these patients are given the diagnosis non-ulcer dyspepsia or functional dyspepsia. Hypersecretion of gastric acid and the bacteria Helicobacter pylori, which seem to be major aetiologic factors in duodenal ulcer, are not important in functional dyspepsia. In these patients gastric motor abnormalities and visceral hypersensitivity are the most important pathophysiological mechanisms. The gastric motility is influenced by stress; there is a strong relationship between anxiety, depression and functional dyspepsia. Antacids, H2-blockers and prokinetics are hardly more effective than placebo in patients with functional dyspepsia, while antidepressants have been proven effective in reducing dyspeptic symptoms. Likewise, psychological treatment like bio-feedback, stress management, interpersonal psychotherapy and cognitive therapy has also been proven effective in reducing dyspeptic symptoms in patients with functional dyspepsia.