The object of this study was to assess the degree of patient information of subjects referred for coronary angiography and their reaction to a detailed protocol of information. The enquiry was performed in 3 stages: an oral evaluation of the degree of information with a standardised questionnaire; the giving of written documents from the French Federation and Society of Cardiology mentioning the risks of the procedure; the continuation of the interview with evaluation of the degree of satisfactions with the information provided. Two hundred and thirty one patients referred by cardiologists for non-urgent coronary angiography were interrogated (175 men, 56 women; mean age 63 years, range: 27-83 years). In the 164 subjects who had never had this investigation: 56 (34.1%) did not appreciate the invasive nature of the procedure 111 (67.6%) totally ignored the risks of the procedure 70 (42.6%) were not informed of the possibility of a surgical procedure or of an angioplasty as a result of the procedure. 89% were satisfied with the information concerning the risks of the investigation. In a second group of 100 patients, the comprehension of the information was checked by the same questionnaire used a posteriori. These results show that patient information is very often incomplete. Despite some reticence, the new procedures seem to be globally well accepted but would be more effective if used before hospital admission.