Primary chronic venous disorders, which according to the CEAP classification are those not associated with an identifiable mechanism of venous dysfunction, are among the most common in Western populations. Varicose veins without skin changes are present in about 20% of the population while active ulcers may be present in as many as 0.5%. Primary venous disorders are thought to arise from intrinsic structural and biochemical abnormalities of the vein wall. Advanced cases may be associated with skin changes and ulceration arising from extravasation of macromolecules and red blood cells leading to endothelial cell activation, leukocyte diapedesis, and altered tissue remodeling with intense collagen deposition. Laboratory evaluation of patients with primary venous disorders includes venous duplex ultrasonography performed in the upright position, occasionally supplemented with plethysmography and, when deep venous reconstruction is contemplated, ascending and descending venography. Primary venous disease is most often associated with truncal saphenous insufficiency. Although historically treated with stripping of the saphenous vein and interruption and removal of major tributary and perforating veins, a variety of endovenous techniques are now available to ablate the saphenous veins and have generally been demonstrated to be safe and less morbid than traditional procedures. Sclerotherapy also has an important role in the management of telangiectasias; primary, residual, or recurrent varicosities without connection to incompetent venous trunks; and congenital venous malformations. The introduction of ultrasound guided foam sclerotherapy has broadened potential indications to include treatment of the main saphenous trunks, varicose tributaries, and perforating veins. Surgical repair of incompetent deep venous valves has been reported to be an effective procedure in nonrandomized series, but appropriate case selection is critical to successful outcomes.