Since its introduction in 1999 and FDA approval in 2002, endovenous laser ablation has been widely accepted to effectively treat superficial venous reflux, with minimal side effects. Anatomically, any combination of superficial, perforator and deep venous disease can result in various stages of chronic venous insufficiency. In general, when multiple levels of venous disease are involved the manifestations of venous insufficiency increase in severity. Given that one patient with significant reflux in deep system will have no resultant symptoms, while another patient may progress to an active ulceration from a saphenous reflux alone, individual treatment strategies in the patient with multilevel reflux disease should be based on a thorough clinical and duplex evaluation to determine their specific anatomy and pathology. A basic understanding of mechanism of laser-tissue interaction, venous pathophysiology and the relationship of deep to superficial reflux disease assists in refining procedural techniques and strategies.