Eight children were recognized to have Turner's syndrome, among 353 patients over 1 year of age who had undergone surgical treatment for coarctation of the aorta. Of these eight children, three developed a significant perioperative hemorrhage from aortic rupture, resulting in one death and one instance of paraparesis related to a period of prolonged hypotension. In two of the other five patients with Turner's syndrome, a decision was made to perform an angioplasty rather than a resection of the coarctation because of apparent friability of the aortic wall. In contrast, only one of the 345 patients without Turner's syndrome died as a result of surgical treatment, and none developed spontaneous perioperative aortic rupture or neurologic deficit. This experience suggests that the operative risk for coarctation of the aorta in this subgroup of patients is considerably greater than that in patients without Turner's syndrome (p < 0.001). Special precautions should include use of rubber-jaw vascular clamps, choice of technique to avoid tension at the anastomotic suture line, and careful control of systemic blood pressure intraoperatively and postoperatively. Indications for surgical treatment of coarctation as well as the type of operative procedure must be individualized cautiously in patients with Turner's syndrome.