Eleven hundred and thirty-eight patients suspected of carotid artery disease were examined prospectively by ultrasound-Doppler. In 39 cases, intra-arterial digital subtraction arteriography was performed as well as well and compared to ultrasound Doppler examination. The overall accuracy was 80% (kappa: 0.65). Discrimination between normal and diseased vessels could be made with an accuracy of 93% (kappa: 0.70) and the accuracy when separating vessels into greater or less than 50% stenosis was 88% (kappa: 0.74). Sources of error are discussed and the paper concludes that colour-Doppler examination is an accurate method for assessment of the carotid artery.