Many systems have been proposed to evaluate the functional incapacity caused by chronic cardiac failure. The classification of the New York Heart Association (NYHA) is the best known. It is subjective, poorly reproducible and has a poor predictive value on effort. The authors propose a Specific French Scale of Activity with the object of a more accurate functional evaluation of cardiac failure, easier to use by the doctor and more specific to French patients and their life styles. A French multicentre study was set up in hospital departments by the French Society of Cardiology working group on Cardiomyopathy and Cardiac Failure to assess this new classification with respect to the NYHA classification and peak VO2 (Weber's classification). Eight centres participated in the study. A total of 124 patients with chronic cardiac failure and a mean age of 61 years (102 men) were included. Cardiac failure was due to ischaemic heart disease in 72 cases, hypertension in 10 cases, dilated cardiomyopathy in 40 cases and aortic regurgitation in 2 cases. Eighty-two patients underwent a double evaluation using the French Scale: 40 patients by 2 physicians and 42 patients by a physician and a nurse. Good reproducibility was found between the assessment by the 2 physicians in 35 cases (87%) and between the physician and nurse in 30 cases (71%). When compared with peak VO2, the classification was concordant in 47% of cases using the NYHA and in 61% of cases using the French Scale, with variation of one class in 40% of cases with the NYHA and 35% of cases with the French Scale. These results show good reproducibility and correspondence of classification with the exercise test which was better using the French Scale than the NYHA classification.