Foam sclerotherapy is the first line of treatment for patients with venous malformations and other venous conditions. Detergent sclerosing agents are tensoactive surfactants that create cellular lysis in the phlebotelium, exposing the subendothelium and acting as a Velcro effect that results in vein obliteration. Surfactants (detergents) promote a liquid transformation from a solution to a gas state against gravity. This phenomenon is described as the Marangoni effect, primarily used in enology to determine the characteristics of wine by describing its legs. We can adapt some of these physical principles into venous therapy by knowing and eventually dominating each sclerosing agent’s specific action and dynamics.