The study compared, by a prospective, randomized method, 6 treatment options: A: Sclerotherapy; B: High-dose sclerotherapy; C: Multiple ligations; D: Stab avulsion; E: Foam-sclerotherapy; F: Surgery (ligation) followed by sclerotherapy. Results were analyzed 10 years after inclusion and initial treatment. Endpoints of the study were variations in ambulatory venous pressure (AVP), refilling time (RT), presence of duplex-reflux, and number of recurrent or new incompetent venous sites. The number of patients, limbs, and treated venous segments were comparable in the 6 treatment groups, also comparable for age and sex distribution. The occurrence of new varicose veins at 5 years varied from 34% for group F (surgery + sclero) and ligation (C) to 44% for the foam + sclero group (E) and 48% for group A (dose 1 sclero). At 10 years the occurrence of new veins varied from 37% in F to 56% in A. At inclusion AVP was comparable in the different groups. At 10 years the decrease in AVP and the increase in RT (indicating decrease in reflux), was generally comparable in the different groups. Also at 10 years the number of new points of major incompetence was comparable in all treatment groups. These results indicate that, when correctly performed, all treatments may be similarly effective. "Standard," low-dose sclerotherapy appears to be less effective than high-dose sclero and foam-sclerotherapy which may obtain, in selected subjects, results comparable to surgery.