Functional (nonulcer) dyspepsia refers to upper abdominal pain or discomfort with or without symptoms of early satiety, nausea, or vomiting with no definable organic cause. The current Rome II criteria help to diagnose functional dyspepsia and avoid misdiagnosis of gastroesophageal reflux disease and irritable bowel syndrome as functional dyspepsia. Assessment of gastric emptying with scintigraphy or breath testing may be useful in identifying delayed gastric emptying in patients with dyspeptic symptoms and may be helpful in patient management. Electrogastrography is a noninvasive test that evaluates for gastric dysrhythmias. Satiety testing is being evaluated as an indirect test for impaired fundic relaxation and visceral hypersensitivity. The symptom response to Helicobacter pylori therapy in patients with functional dyspepsia and a negative endoscopy examination but a positive H. pylori test is marginal. Lifestyle modifications often are suggested for initial treatment of functional dyspepsia. Dietary changes such as frequent small meals, low-fat diet, and avoidance of certain aggravating foods may improve symptoms. Additional measures include cessation of smoking, avoiding excess alcohol intake, and minimizing coffee intake. Antacids and over-the-counter histamine type 2 receptor antagonists may be helpful as an "on-demand" therapy for intermittent symptoms. They are safe and relatively inexpensive. Different subgroups of functional dyspepsia are based on the predominant symptom and may help in choosing an appropriate drug to initiate therapy. If the predominant symptom is epigastric pain (ulcer-like functional dyspepsia), histamine-2 receptor antagonists or proton pump inhibitors are the initial treatment of choice. If fullness, bloating, early satiety or nausea is the predominant complaint (dysmotility-like functional dyspepsia), a prokinetic agent may help. Metoclopramide is the only available effective prokinetic agent at present. If metoclopramide is used, short-term treatment and discussion of possible side effects with the patient are advised. If there is no response to these initial treatments, switching therapy from proton pump inhibitor to prokinetic or vice versa can be tried. If these treatment options fail, patient re-evaluation for other disorders (including other functional bowel disorders) is advised. A low-dose tricyclic antidepressant at bedtime may be helpful for treatment of visceral hypersensitivity.