One hundred consecutive patients who had consulted their general practitioner because of upper abdominal pain related to eating, were investigated after initial interviews by the general practitioner, a medical registrar and the same consultant physician. Thirty seven had active upper gastrointestinal or biliary tract diseases, including 29 with peptic ulcers. The general practitioner and consultant correctly distinguished between organic and non-organic dyspepsia (NOD) in 51 and 65 cases respectively. Although the sensitivity of the general practitioner diagnosis of organic disease was high (95%), the specificity (23%) and predictive value (42%) were low. There were fewer organic diagnoses amongst the patients under the age of 30 (P less than 0.05) and those with symptoms for less than 3 months (P less than 0.01). No patient under 30 with symptoms for less than 3 months had organic dyspepsia. We suggest that if dyspeptic patients over the age of 30 and those under 30 with symptoms for longer than 3 months are investigated, about one-third will be found to have organic diseases.