An unusual anomaly of the aorta, characterized by a sharp anterior angulation of the aortic arch at the level of the ligamentum arteriosum, has been variously termed pseudocoarctation, subclinical coarctation, and kinking or buckling of the aorta. This may be an isolated anomaly, or it may be associated with other congenital cardiac defects. The physical, roentgenographic, and angiographic findings may be difficult to distinguish from true coarctation of the aorta. Four children with pseudocoarctation of the aorta are reported. Two of the four patients underwent unnecessary exploratory thoracotomy. The absence of systemic hypertension, collateral circulation, and a significant gradient across the aortic isthmus plus a lateral aortogram revealing a sharp defect along the posterior wall of the aorta with preservation of the normal anterior margin should differentiate pseudocoarctation from true coarctation of the aorta.