Treatment of incompetent perforating veins (IPVs) remains controversial in chronic venous insufficiency (CVI), because the evidence of its efficacy is of moderate quality and is not supported by prospective randomized trials without important limitations. In an excellent review of the subject, O’Donnell 1 recently concluded that the role of IPV ablation alone or concomitant with ablation of the great saphenous vein remains uncertain and awaits results of properly conducted randomized and controlled trials. Incompetent perforating veins, however frequently contribute to hemodynamic alterations in CVI. The size of perforating veins increases in patients with increasing severity of chronic venous disease (CVD), likely due to the elevated venous volume and venous pressures. There is a correlation between the number and size of IPVs and the severity of CVI. Also, the duration of reflux is longer in patients with more advanced disease. Documenting the hemodynamic significance of IPVs is difficult, because isolated IPVs cause CVD in less than 5% of patients. It is estimated that about 70% of IPVs in patients with CVD have hemodynamic significance. Evidence of Clinical Benefit From Perforator Interruption Patients with advanced CVI with duplex evidence of IPVs and patent deep veins are candidates for perforator interruption, either combined with superficial ablation or used as a staged procedure. Although initially performed with an open surgical technique, this has been replaced by several minimally invasive approaches, including subfascial endoscopic perforator surgery and percutaneous ablation using sclerosants or thermal mechanisms.