The problem of the classification of varicose veins is as old as phlebology itself. A number of attempts have been made to define and assess this anatomical entity, which is progressively better investigated and better treated. Chronic venous insufficiency is a more recent pathophysiological concept, which covers both superficial venous lesions and deep lesions, regardless of their cause and their expression, especially trophic, unequivocal and dominant. A brief review of the principal classifications clearly demonstrates the difficulty of reaching a consensus. The precise definition of varicose veins and chronic venous insufficiency suggests the proposal of a simple clinical classification into five stages of chronic venous insufficiency. Beyond stage II of symptomatic varicose veins, treatment is required and complementary investigations, especially functional, are justified.