Gastroparesis occurs frequently and may be associated with gastrointestinal symptoms, impaired oral drug absorption and, in diabetic patients, poor blood glucose control. Although current knowledge of the mechanisms responsible for delayed gastric emptying is limited, it is clear that gastroparesis arises from a spectrum of motor dysfunctions. There is a poor correlation between symptoms and delay in gastric emptying, and objective measurement is therefore required for the diagnosis of gastroparesis. Scintigraphic measurement of gastric emptying is at present the only clinically applicable method, although other techniques, particularly radioisotopic breath tests and ultrasound, show considerable promise. Therapy with the prokinetic drugs, cisapride, domperidone, metoclopramide, and erythromycin, forms the mainstay of treatment. Although there have been few formal comparisons, cisapride is considered to be the drug of first choice. Current knowledge of the etiology, pathophysiology, investigation, and treatment of gastroparesis is discussed in this review.