Data were analyzed from 581 consecutive cases of thoracoabdominal aortic aneurysm (TAAA) repairs. Preoperatively, 32 patients (6%) had only one functioning kidney (single-kidney group), and 549 patients (94%) had tow functioning kidneys (reference group). The patients' mean age was higher in the reference group (64.9 years, range: 21-85) than in the single-kidney group (63.2 years, range: 38-79); p < 0.05. However, there was a significantly higher incidence of hypertension (97% versus 78%), coronary artery disease (50% versus 34%), and renal artery stenosis ipsilateral to functioning kidneys (88% versus 26%) in the single-kidney group than in the reference group; p < 0.05. Preoperatively, renal insufficiency (serum creatinine > or = 2.5 mg/dl or patients on dialysis) was present in four patients (13%) in the single-kidney group and in 21 patients (4%) in the reference group; p < 0.05. In the former group, the unilateral loss of kidney function was secondary to atrophy in 30 patients (94%) and agenesis in two patients (6%). The simple clamp-open distal anastomosis technique was employed in the majority of the cases in the single-kidney group (91%) and in the reference group (83%); p > 0.05. Renal artery endarterectomy or bypass ipsilateral to functioning kidneys was performed on 18 patients (56%) in the single-kidney group and 68 patients (12%) in the reference group; p < 0.05. Renal perfusion with cold Ringer's lactate solution was done in 18 cases (56%) in the single-kidney group and 228 cases (42%) in the reference group; p > 0.05. There was no difference in the operative mortality (9% versus 7%) and the incidence of paraplegia/paraparesis (6% versus 5%) between the single-kidney group and the reference group; p > 0.05. Postoperatively, new onset renal insufficiency developed in 10 patients (31%) in the single-kidney group, and 58 patients (11%) in the reference group; p < 0.05. In the single-kidney group, four patients (13%) had mild renal dysfunction (serum creatinine > or = 2.5 mg/dl), and two patients (6%) were on dialysis on discharge. Notably, there was no significant difference in the incidence of renal insufficiency on admission compared to the incidence of renal insufficiency on discharge in the single-kidney group (13% versus 19%; p > 0.05). TAAA repair in patients with one functioning kidney can be performed safely. Postoperative renal insufficiency can be managed successfully in the majority of patients.