An automatic measuring apparatus for recording blood pressure employing oscillometry was used to measure mean and elastic systolic and diastolic perfusion pressures in the ankles of arteritic patients. The reliability of the method was tested in 100 cases. Correlations with reference pressures measured by non-invasive techniques (ultrasonographic and plethysmographic) were good. The reliability and reproducibility of the apparatus employed (Dinamap) were in conformity with the desired maximum error (less than 15%). It is hoped that this method will allow improved evaluation of lower limb circulation, and the definition of a sliding scale of the indices of mean and elastic systolic and diastolic pressures. The major cause of error appears to be lack of pulsation in the leg arteries.