The treatment of varicose veins has traditionally been ablative in nature and implemented without intent to improve the haemodynamic condition of the lower extremity veins. Haemodynamic surgery attempts to treat varicose veins by changing the reflux pattern while preserving the most efficient venous drainage channels. To implement this treatment modality it is necessary to have a clear understanding of the physiologic principles and the different reflux patterns that form the basis of haemodynamic surgery. Haemodynamic surgery is an emerging treatment for varicose veins, and has received little attention in the English literature. The rationale, and functional and anatomic basis of haemodynamic surgery for varicose veins are herein described. (C) 2003 Royal Society of Medicine Press.