Aortic regurgitation (AR) is a common clinical disease associated with significant morbidity and mortality. Investigations based largely on non-invasive imaging are pivotal in discerning the severity of disease and its impact on the heart. Advances in technology have contributed to improved risk stratification and to our understanding of the pathophysiology of AR. Surgical aortic valve replacement is the predominant treatment. However, its use is limited to patients with an acceptable surgical risk profile. Transcatheter aortic valve implantation is an alternative treatment. However, this therapy remains in its infancy, and further data and experience are required. This review article on AR describes its prevalence, mechanisms, diagnosis and treatment.