Abstract: The present invention relates to a method for treating varicose veins, which comprises: pre-treating a target vein segment with a pulsed laser radiation having a wavelength of from 1400 to 2300 nm, thereby causing a substantial diameter reduction of the target vein segment; delivering a sclerosing agent to the pre-treated target vein segment, thereby causing occlusion of the vein. The sclerosing agent is preferably a foam sclerosing agent. The above method in particularly effective also for larger veins, especially veins exceeding 10 mm of diameter, without causing major discomfort to the patients, and which has a very limited risk of side effects, such as those deriving from the injection of relatively large amounts of sclerosing agent or from damages to the vessel endothelium.