A system and method are provided that are capable of selectively treating a vein using photothermolysis techniques, where an electromagnetic radiation is applied to tissue containing the vein. The radiation can be selected so that it may be more effectively absorbed by veins as compared to arteries. Thus, unwanted thermal damage to arteries in the vicinity of the vein being treated can be reduced or avoided. The radiation can have a frequency of approximately 654 nm, which can provide a ratio of absorption by veins to absorption by arteries of about 3.7. Other wavelengths near 654 nm may be provided, for example, which can have an absorption ratio greater than, e.g., about 3.3 to 3.6.