Coarctation of the abdominal aorta constitutes a rare group of vascular abnormalities, including segmental stenoses and extended hypoplasia. Hypertension is the usual solitary clinical finding and contrasts with the diversity of anatomic lesions and surgical techniques used for treatment. It is often difficult to determine whether the lesion is congenital or due to Takayasu's aortitis. Three cases of hypoplasia in adolescents are reported. Treatment consisted of an aortoaortic bypass in all cases. Vein angioplasty of the renal arteries was performed concomitantly in one case of inter- and infrarenal hypoplasia associated with stenosis of the two renal arteries. In one of the two cases of suprarenal hypoplasia, the celiac axis was reimplanted after excision of an associated aneurysm. In all three cases, blood pressure returned to normal values without medical treatment.