The excess risk of cardiovascular disease in patients with Type 2 diabetes mellitus remains largely unexplained. Arterial stiffness, an early feature of diabetic vasculopathy involving several mechanisms, results in impaired arterial compliance, and has recently been proposed as a powerful independent predictor of cardiovascular disease. Increased arterial stiffness can contribute to the development and progression of hypertension, left ventricular hypertrophy and dysfunction, and to decreased myocardial perfusion, all of which are highly prevalent in Type 2 diabetes mellitus. Large artery stiffening has been demonstrated in Type 2 diabetes using several different methods including measurement of central pulse wave velocity, or estimation of aortic compliance, a technically demanding technique requiring the simultaneous measurement of stroke volume and diastolic pressure decay. Increased arterial stiffness of smaller arteries is also an important contributor to systemic arterial stiffness and cardiovascular risk. Increasing demand by clinical researchers for measurement of arterial stiffness has led to the development and commercial availability of highly practicable techniques. These new techniques, which utilise different aspects of the pulse pressure waveform, are simple, reliable and reflect both large and small vessel stiffness. They offer new tools for identifying patients at increased risk of developing cardiovascular complications including those with established diabetes. In this article we introduce the reader to the concepts of arterial stiffness, the significance of arterial stiffness for diabetes, and the new techniques that may potentially be useful for clinical researchers or practitioners.