Animal models of large artery wall stiffness fall into two categories: firstly those that slowly develop multifactorial vascular dysfunction spontaneously, such as the ageing rat. The second type of model consists of those in which a specific pathology is induced by surgical, chemical, or genetic means. Such models are based on a short-term, highly traumatic insult to the arterial wall of a young animal and its acute reaction to such insult. This is very different from the human situation in which changes in wall stiffness arise from the long-term accumulation of relatively minor episodes of vascular insult in the vulnerable elderly.