The distinction between precordial pain of cardiac origin and pain of extra-cardiac origin is a daily problem. We wanted to study the value of echocardiography in this difficult diagnostic problem. In a series of 148 patients admitted to the unit in 1982 for chest pain. 104 were investigated by echocardiography and coronary angiography. In 36 per cent of patients, the echocardiogram was normal and was unable to predict the presence or absence of coronary artery disease. Further investigations seem to be justified in these cases. In 57 per cent of cases, the echocardiogram was abnormal, suggestive of a cardiac cause for the pain. The demonstration of a disorder of segmental kinetics in the left ventricle is suggestive of coronary artery disease, which is detected 82 per cent of cases and is a good indication for coronary angiography. The other abnormalities detected, mitral valve prolapse, hypertrophic cardiomyopathy and dilated cardiomyopathy are rarely associated with coronary artery disease, which was found in 0, 13 and 14 per cent of cases, respectively. Initially, these abnormalities may be sufficient to explain the symptomatology. Pericardial detachments are associated with coronary artery lesions in 50 per cent of cases and should be very carefully monitored.