Traditionally, strain gauge technique is used in Denmark to measure ankle blood pressure, a method requiring both time and well-trained personnel. In a study involving 90 limbs in 45 patients, this method was compared with ultrasonic technique using a portable 5 MHz Doppler. The reproducibility of Doppler ankle pressure measurement was similar to that found in strain gauge based studies. Two consecutive measurements may differ by 20 mmHg or in terms of ankle-brachial index by 0.15 before this is considered significant. No systematic variation was found between the two methods. Increasing difficulties were encountered with the Doppler technique at pressures below 50 mmHg. It is concluded that Doppler is a good alternative to strain gauge for measurement of ankle blood pressure.