Arterial augmentation indices (AI, the ratios of differences in the components of arterial pressure during systole to pulse pressure) provide measures of pressure wave reflection and are usually estimated from arterial tonometry. High resolution ultrasound tracking of the arterial wall provides an alternative method for obtaining AI. The objective of the present study was to compare AI measured by tonometry and wall tracking at the carotid, brachial and radial arteries. Forty seven asymptomatic subjects (24 men), aged 23–84 years were studied. At each site, tonometry (SphymoCor system, Atcor medical, Australia) and wall tracking (Aloka α10 ultrasound system with a 10MHz linear vascular transducer, Aloka, Japan) were performed in triplicate in random order. At the carotid artery, there was reasonably good agreement between AI obtained by wall tracking and tonometry (R=0.82, P<0.0001, mean difference±SD, 3.0±13.7%) but at brachial and radial sites agreement was poor (R=0.33, mean difference±SD, 17.7±24.2% at brachial, R=0.48, mean difference, 18.1±23.5% at radial). Wall tracking may be a reasonable surrogate for tonometry when measuring AI at the carotid artery but there is poor agreement between AI obtained by tonometry and wall tracking in smaller arteries.