Fifty-two consecutive patients referred to a psychiatrist with somatic symptoms of underlying psychiatric disorder were studied. The costs of investigations performed in the general hospital prior to referral to the psychiatrist were assessed. The median cost was pounds 286 but the range was pounds 25-2300. Those costs were determined by the physician's original assessment of the likelihood of organic disease and were independent of the view expressed in the general practitioner's referral letter. This preliminary study indicates the need to understand more fully the determinants of early or late referral of somatization patients to a psychiatrist. The determinants include the diagnostic difficulties of the presenting symptom, patient factors including resistance to adopting a psychological view of the symptoms, and physician factors determining the number of investigations performed to exclude organic disease.