Coronary artery aneurysms are defined as coronary dilations as greater than 1.5 times the largest diameter of the adjacent coronary segment. They are a relatively rare finding on coronary angiography, with prevalence ranging from 0.3% to 5% depending on case series. The identification of a coronary artery aneurysm is often a dilemma for both the clinician and the interventionist in terms of diagnosis, treatment and follow-up. This review summarizes the etiologic, pathogenetic, clinical and therapeutic aspects of coronary artery aneurysms in the light of the latest research on this topic.